TECHNICAL FIELD
[0001] The present invention relates to an electrophotographic photosensitive member, a
method of manufacturing the electrophotographic photosensitive member, and a process
cartridge and an electrophotographic apparatus each having the electrophotographic
photosensitive member.
BACKGROUND ART
[0002] Electrophotographic photosensitive members using organic photoconductive substances
(organic electrophotographic photosensitive members) have been intensively studied
and developed in recent years.
[0003] The electrophotographic photosensitive member is basically composed of a support
and a photosensitive layer formed on the substrate. In the case of the organic electrophotographic
photosensitive member, a photosensitive layer is formed using a charge-generating
substance and a charge-transporting substance as photoconductive substances and a
resin for binding these substances (binder resin).
[0004] There are two types of layer structure of the photosensitive layer: a multilayer
type and a monolayer type. In the multilayer type one, the function of charge generation
and the function of charge transfer are separated (functionally separated) into a
charge-generating layer and a charge-transporting layer, respectively. In the monolayer
type one, a single layer is provided with both the function of charge generation and
the function of charge transfer.
[0005] Most of electrophotographic photosensitive members employ a multilayer type photosensitive
layer. In many cases, the charge-transporting layer is provided as the surface layer
of the electrophotographic photosensitive members.
[0006] The image formation using an electrophotographic apparatus is generally carried out
as described below.
[0007] First, an electrophotographic photosensitive member is elecrostatically charged and
the charged electrophotographic photosensitive member is then irradiated with exposure
light, thereby forming an electrostatic latent image on the electrophotographic photosensitive
member. Subsequently, the electrostatic latent image is developed with a toner-containing
developer and a toner image thus formed is then transferred from the electrophotographic
photosensitive member to a transfer material (such as paper). The transfer material
with the transferred toner image is subjected to a process of an image fixation and
then discharged from the apparatus to the outside. On the other hand, the electrophotographic
photosensitive member after the transfer process is subjected to a cleaning process
so that the transfer residual toner is removed from the member, and the member is
then subjected to the removal of electricity if required, followed by subjecting the
electrophotographic photosensitive member to a subsequent cycle of image formation.
[0008] Further, reflecting the needs of high image qualities in recent years, the number
of electrophotographic apparatuses each employing spherical toner produced by a suspension
polymerization method or an emulsion polymerization method has increased. For example,
in a process of wiping out the transfer residual toner, a cleaning member (such as
a cleaning blade), which is brought into contact with the electrophotographic photosensitive
member, may hardly prevent the toner from slipping therethrough because of the surface
smoothness of such spherical toner.
[0009] For alleviating the slip of toner, the cleaning member should be optimized on the
basis of the specifications of an electrophotographic apparatus. In other words, there
is a need of increasing the contact pressure of the cleaning member to be applied
on the electrophotographic photosensitive member, the flexibility of the mounting
angle of the cleaning member, or the flexibility of designing the configuration of
the cleaning member.
[0010] Under the operation of an electrophotographic apparatus, a cleaning blade may abnormally
slide on an electrophotographic photosensitive member and sometimes cause the so-called
"blade-curling" where the blade turns up.
[0011] The blade-curling may tend to occur at an early stage after the setting of the electrophotographic
apparatus before the accumulation of the transfer residual toner (it functions as
a powder to impart slidability between the cleaning blade and the electrophotographic
photosensitive member) on the contact boundary surface between the cleaning blade
and the electrophotographic photosensitive member. When the material of the cleaning
blade is an elastic rubber material, a high-temperature, high-humidity environment
may tend to increase the frequency at which the curling of the blade occurs.
[0012] Therefore, for avoiding the generation of such blade-curling, the addition of an
additive to the surface layer of an electrophotographic photosensitive member may
intensively improve the flexibility of blade design. For instance, the improvement
may be attained by a method involving adding a compound as disclosed in Japanese Patent
Application Laid-Open No.
S62-014657.
[0013] However, the function of the additive is to improve the slidability of a cleaning
blade to prevent it from turning up, so the additive has been also desired to be inactive
to the electrophotographic properties of the electrophotographic photosensitive member
(i.e., not prevent electric charge from moving through the photosensitive layer).
[0014] By the way, Japanese Patent Application Laid-Open No.
S58-164656 discloses a fluorine graft polymer with a linear fluoroalkyl group.
[0015] Further, Japanese Patent Application Laid-Open No.
2003-012588 discloses a fluorine-containing polymer with a trifluoromethyl group on any one of
its side chains and an ether structure.
DISCLOSURE OF THE INVENTION
[0016] The present invention aims to provide an electrophotographic photosensitive member
having good electrophotographic properties while being prevented from the generation
of blade-curling, a method of manufacturing the electrophotographic photosensitive
member, and a process cartridge and an electrophotographic apparatus each having the
electrophotographic photosensitive member.
[0017] The inventors of the present invention have found out the following facts as a result
of investigation.
[0018] That is, out of the additives for taking measures against blade-curling, a fluorine
graft polymer as described in Japanese Patent Application Laid-Open No.
58-164656 may be incorporated in the surface layer of an electrophotographic photosensitive
member to obtain a good blade-curling preventing effect.
[0019] Further, in addition to the blade-curling preventing effect, improvements in electrophotographic
properties can be also attained by improving the fluorine graft polymer described
in Japanese Patent Application Laid-Open No.
58-164656, specifically modifying the linear chain structure on the fluoroalkyl group of the
compound to a specific structure.
[0020] That is, according to one aspect of the present invention, an electrophotographic
photosensitive member has a support and a photosensitive layer formed on the substrate
and is
characterized in that the surface layer of the photosensitive member contains a polymer having repetitive
structural units each represented by the following formula (1):
(where R
1 represents a hydrogen atom or a methyl group, R
2 represents a single bond or a divalent group, and Rf
1 represents a monovalent group having at least one of a fluoroalkyl group and a fluoroalkylene
group), and that 70 to 100% by number of the repetitive structural units each represented
by the above formula (1) in the polymer are each any of repetitive structural units
represented by the following formulae (1-1) to (1-6):
(where R
1 represents a hydrogen atom or a methyl group, R
20 represents a single bond or an alkyl group, R
21 represents an alkylene group having a branched structure with a carbon-carbon bond,
R
22 represents a - R
21- group or a -O-R
21- group, R
23 represents a -Ar-group, a -O-Ar- group, or a -O-Ar-R- group (Ar represents an arylene
group and R represents an alkylene group), Rf
10 represents a monovalent group having at least a fluoroalkyl group, Rf
11 represents a fluoroalkyl group having a branched structure with a carbon-carbon bond,
Rf
12 represents a fluoroalkyl group interrupted with oxygen, and Rf
13 represents a perfluoroalkyl group having 4 to 6 carbon atoms).
[0021] According to another aspect of the present invention, a method of manufacturing the
above electrophotographic photosensitive member is characterized by forming the surface
layer of the electrophotographic photosensitive member using a surface-layer coating
solution containing a polymer having repetitive structural units each represented
by the above formula (1).
[0022] According to another aspect of the present invention, a process cartridge is characterized
by including: the above electrophotographic photosensitive member; and at least one
unit selected from the group consisting of a charging unit, a developing unit, and
a cleaning unit, wherein the member and the at least one unit are integrally supported
and detachably attached to the main body of an electrophotographic apparatus.
[0023] According to another aspect of the present invention, an electrophotographic apparatus
is characterized by including: the electrophotographic photosensitive member; a charging
unit; an exposing unit; a developing unit; and a transfer unit.
[0024] According to the present invention, there may be provided an electrophotographic
photosensitive member which is prevented from the generation of blade-curling while
having good electrophotographic properties, a method of manufacturing the electrophotographic
photosensitive member, and a process cartridge and an electrophotographic apparatus
each having the electrophotographic photosensitive member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025]
FIG. 1A, FIG. 1B, FIG 1C, FIG. 1D, and FIG. 1E are diagrams that illustrate examples
of the layer structure of an electrophotographic photosensitive member of the present
invention.
FIG. 2 is a diagram that schematically illustrates the configuration of an electrophotographic
apparatus provided with a process cartridge of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0026] Hereinafter, the present invention will be described in more detail.
[0027] An electrophotographic photosensitive member of the present invention is prevented
from the generation of blade-curling at an early stage and keeps electrophotographic
properties in a favorable condition. Here, the term "at an early stage" is a time
period before the sufficient accumulation of transfer residual toner (it functions
as a powder to impart slidability between the cleaning blade and the electrophotographic
photosensitive member) on the contact boundary surface between the cleaning blade
and the electrophotographic photosensitive member. The present invention can attain
the above object by allowing the surface layer of the electrophotographic photosensitive
member to contain the above polymer with a specific repetitive structural unit.
[0028] The above polymer having a specific repetitive structural unit is a polymer having
repetitive structural units each represented by the following formula (1) :
(where R
1 represents a hydrogen atom or a methyl group, R
2 represents a single bond or a divalent group, and Rf
1 represents a monovalent group having at least one of a fluoroalkyl group and a fluoroalkylene
group), in which 70 to 100% by number of the repetitive structural units each represented
by the above formula (1) in the polymer are each any of repetitive structural units
represented by compounds represented by the following formulae (1-1) to (1-6):
(where R
1 represents a hydrogen atom or a methyl group, R
20 represents a single bond or an alkyl group, R
21 represents an alkylene group having a branched structure with a carbon-carbon bond,
R
22 represents a - R
21- group or a -O-R
21- group, R
23 represents a -Ar-group, a -O-Ar- group, or a -O-Ar-R- group (Ar represents an arylene
group and R represents an alkylene group), Rf
10 represents a monovalent group having at least a fluoroalkyl group, Rf
11 represents a fluoroalkyl group having a branched structure with a carbon-carbon bond,
Rf
12 represents a fluoroalkyl group interrupted with oxygen, and Rf
13 represents a perfluoroalkyl group having 4 to 6 carbon atoms).
Re: Formula (1)
[0029] R
1 in the above formula (1) represents a hydrogen atom or a methyl group.
[0030] R
2 in the above formula (1) represents a single bond or a divalent group. The divalent
group may be preferably one having at least an alkylene group or an arylene group
in its structure. Examples of the alklyene group include: linear alkylene groups such
as a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene
group, and a hexylene group; and branched alkylene groups such as an isopropylene
group and an isobutylene group. Of those, the methylene group, the ethylene group,
the propylene group, and the butylene group are preferable. Examples of the arylene
group include a phenylene group, a naphthylene group, and a biphenylene group. Of
those, the phenylene group is preferable.
[0031] In the above formula (1), Rf
1 represents a monovalent group having at least one of a fluoroalkyl group and a fluoroalkylene
group. Examples of the fluoroalkyl groups include the following:
[0032] Examples of the fluoroalkylene group include the following:
Re: Formula (1-1)
[0033] R
1 in the above formula (1-1) represents a hydrogen atom or a methyl group.
[0034] R
20 in the above formula (1-1) represents a single bond or an alkylene group. Examples
of the alkylene group include linear alkylene group such as a methylene group, an
ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene
group. Of those, the methylene group, the ethylene group, the propylene group, and
the butylene group are preferable.
[0035] Rf
11 in the above formula (1-1) represents a fluoroalkyl group having a branched structure
with a carbon-carbon bond. Here, the branched structure with a carbon-carbon bond
represents a structure in which the longest bonding chain and side chains thereof
are bonded with each other by carbon-carbon bonds. In addition, part or the whole
of the longest bonding chain and/or the side chains thereof may be substituted with
fluorine.
[0037] Of those, the fluoroalkyl groups represented by the above formulae (Rf11-1), (Rf11-7),
(Rf11-17), and (Rf11-18) are preferable.
[0039] Of those, the repetitive structural units represented by the above formulae (1-1-3),
(1-1-4), (1-1-6), (1-1-7), (1-1-10), (1-1-11), (1-1-13), and (1-1-14) are preferable.
[0040] For obtaining an effect of preventing the blade-curling, it is important that a polymer
having the repetitive structural unit represented by the above formula (1) for the
present invention be a polymer having at least one of the fluoroalkyl group and the
fluoroalkylene group in the repetitive structural unit. Further, the polymer having
the repetitive structural unit represented by the above formula (1) for the present
invention contains repetitive structural units represented by any one of the above
formulae (1-1) to (1-6) in an amount of 70 to 100% by number.
[0041] In the case of the repetitive structural unit as represented by the above formula
(1-1), the inventors of the present invention consider that the effects of the present
invention can result from the lowering of the energy on the surface of an electrophotographic
photosensitive member due to a fluoroalkyl group having a branched structure with
a carbon-carbon bond in the repetitive structural unit represented by the above formula
(1-1).
[0042] Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains the repetitive structural unit represented
by the above formula (1-1) preferably in an amount of 70 to 100% by number, more preferably
in an amount of 90 to 100% by number.
Re: Formula (1-2)
[0043] R
1 in the above formula (1-2) represents a hydrogen atom or a methyl group.
[0044] R
21 in the above formula (1-2) represents an alkylene group having a branched structure
with a carbon-carbon bond. The branched structure with a carbon-carbon bond represents
a structure in which the longest bonding chain and the side chains thereof are bonded
by carbon-carbon bonds. The longest bonding chain is preferably formed of 2 to 6 carbon
atoms. In addition, any substituent on the side chain portion may be an alkyl group,
a fluoroalkyl group, or the like. The alkyl group may be a methyl group, an ethyl
group, a propyl group, or a butyl group. Of those, the methyl group and the ethyl
group are preferable. The fluoroalkyl group may be, for example, any of the groups
represented by the above formulae (CF-1) to (CF-3). Of those, the group represented
by the above formula (CF-1) is preferable.
[0045] Rf
10 in the above formula (1-2) represents a monovalent group with at least a fluoroalkyl
group. Examples of the fluoroalkyl group include the groups represented by the above
formulae (CF-1) to (CF-3). In addition, Rf
10 is not limited to a linear structure but may be of a branched structure. Alternatively,
Rf
10 may be a fluoroalkyl group interrupted with an oxygen atom.
[0047] Of those, a monovalent group having a fluoroalkyl group represented by the above
formula (Rf10-19) or (Rf10-24) is preferable.
[0049] Of those, a repetitive structural unit represented by the above formula (1-2-1) or
(1-2-2) is preferable.
[0050] As described above, for obtaining an effect of preventing the blade-curling, it is
important that a polymer having the repetitive structural unit represented by the
above formula (1) for the present invention be a polymer having at least one of the
fluoroalkyl group and the fluoroalkylene group in the repetitive structural unit.
Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains repetitive structural units represented
by any one of the above formulae (1-1) to (1-6) in an amount of 70 to 100% by number.
[0051] In the case of the repetitive structural unit represented by the above formula (1-2),
the inventors of the present invention have an opinion that the effects of the present
invention can result from lowering of the energy on the surface of the electrophotographic
photosensitive member due to the fluoroalkyl group or fluoroalkylene group in the
repetitive structural unit represented by the above formula (1-2). In addition, the
effect of the alkylene group having a branched structure with a carbon-carbon bond
may lead to an increase in compatibility between the binder resin and the polymer
having the repetitive structural unit represented by the above formula (1) for the
present invention. As a result, the energy on the surface of the electrophotographic
photosensitive member may be lowered by the increased compatibility.
[0052] Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains the repetitive structural unit represented
by the above formula (1-2) preferably in an amount of 70 to 100% by number, more preferably
in an amount of 90 to 100% by number.
Re: Formula (1-3)
[0053] R
1 in the above formula (1-3) represents a hydrogen atom or a methyl group.
[0054] R
22 in the above formula (1-3) represents a -R
21-group or a -O-R
21- group. To be specific, the -R
21-group represents an alkylene group having a branched structure with a carbon-carbon
bond. The branched structure with a carbon-carbon bond represents a structure in which
the longest bonding chain and the side chains thereof are bonded by carbon-carbon
bonds. The longest bonding chain is preferably formed of 2 to 6 carbon atoms. In addition,
the side chain portion may be an alkyl group, a fluoroalkyl group, or the like. The
alkyl group may be a methyl group, an ethyl group, a propyl group, or a butyl group.
Of those, the methyl group and the ethyl group are preferable. The fluoroalkyl group
may be, for example, any of the groups represented by the above formulae (CF-1) to
(CF-3). Of those, the group represented by the above formula (CF-1) is preferable.
Further, the -O-R
21-group represents a structure in which the alkylene group having a branched structure
with a carbon-carbon structure as described above is bonded to Rf
10 through an oxygen atom.
[0055] Rf
10 in the above formula (1-3) represents a monovalent group with at least a fluoroalkyl
group. Examples of the fluoroalkyl group include the groups represented by the above
formulae (CF-1) to (CF-3). In addition, Rf
10 is not limited to a linear structure but may be of a branched structure. Alternatively,
Rf
10 may be a fluoroalkyl group interrupted with an oxygen atom.
[0056] Specific examples of Rf
10 in the above formula (1-3) include those represented by the above formulae (Rf10-1)
to (Rf10-36). Of those, monovalent groups with fluoroalkyl groups represented by the
above formulae (Rf10-10) and (Rf10-19) are preferable.
[0058] Of those, the repetitive structural units represented by the above formulae (1-3-1),
(1-3-2), (1-3-3), (1-3-4), (1-3-6), (1-3-9), (1-3-10), (1-3-11), (1-3-12), and (1-3-14)
are preferable.
[0059] As described above, for obtaining an effect of preventing the blade-curling, it is
important that a polymer having the repetitive structural unit represented by the
above formula (1) for the present invention be a polymer having at least one of the
fluoroalkyl group and the fluoroalkylene group in the repetitive structural unit.
Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains repetitive structural units represented
by any one of the above formulae (1-1) to (1-6) in an amount of 70 to 100% by number.
[0060] In the case of the repetitive structural unit represented by the above formula (1-3),
the inventors of the present invention have an opinion that the effects of the present
invention can result from lowering of the energy on the surface of the electrophotographic
photosensitive member due to the fluoroalkyl group included in the repetitive structural
unit represented by the above formula (1-3). In addition, the alkylene group having
a branched structure with a carbon-carbon bond may lead to an increase in compatibility
between the binder resin and the polymer having repetitive structural unit represented
by the above formula (1) for the present invention. As a result, the energy on the
surface of the electrophotographic photosensitive member may be lowered by the increased
compatibility.
[0061] Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains the repetitive structural unit represented
by the above formula (1-3) preferably in an amount of 70 to 100% by number, more preferably
in an amount of 90 to 100% by number.
Re: Formula (1-4)
[0062] R
1 in the above formula (1-4) represents a hydrogen atom or a methyl group.
[0063] R
23 in the above formula (1-4) represent a -Ar-group, a -O-Ar- group, or a -O-Ar-R- group
(Ar represents an arylene group and R represents an alkylene group). Examples of the
arylene group of Ar include a phenylene group, a naphthylene group, and a biphenylene
group. Of those, the phenylene group is preferable. Examples of the alkylene group
of R include: linear alkylene groups such as a methylene group, an ethylene group,
a propylene group, a butylene group, a pentylene group, and a hexylene group; and
branched alkylene group, such as an isopropylene group and an isobutylene group. Of
those, the methylene group, the ethylene group, the propylene group, and the butylene
group are preferable. The -O-Ar- group or the -O-Ar-R- group represents a structure
to be bonded to Rf
10 through an oxygen atom.
[0064] Rf
10 in the above formula (1-4) represents a monovalent group with at least a fluoroalkyl
group. The fluoroalkyl group may be, for example, a group represented by any of the
above formulae (CF-1) to (CF-3). Further, Rf
10 is not limited to a linear structure but may be of a branched structure. Alternatively,
Rf
10 may be a fluoroalkyl group interrupted with an oxygen atom.
[0065] Specific examples of Rf
10 in the above formula (1-4) include those represented by the above formulae (Rf10-1)
to (Rf10-36). Of those, monovalent groups with fluoroalkyl groups represented by the
above formulae (Rf10-21) and (Rf10-36) are preferable.
[0067] Of those, the repetitive structural units represented by the above formulae (1-4-1),
(1-4-6), (1-4-7), (1-4-8), (1-4-10), (1-4-15), (1-4-16), and (1-4-17) are preferable.
[0068] As described above, for obtaining an effect of preventing the blade-curling, it is
important that a polymer having the repetitive structural unit represented by the
above formula (1) for the present invention be a polymer having at least one of the
fluoroalkyl group and the fluoroalkylene group in the repetitive structural unit.
Further, the polymer having the repetitive structural unit represented by the present
formula (1) for the above invention contains repetitive structural units represented
by any one of the above formulae (1-1) to (1-6) in an amount of 70 to 100% by number.
[0069] In the case of the repetitive structural unit represented by the above formula (1-4),
the inventors of the present invention have an opinion that the effects of the present
invention can result from lowering of the energy on the surface of the electrophotographic
photosensitive member due to the fluoroalkyl group included in the repetitive structural
unit represented by the above formula (1-4). In addition, the effect of the arylene
group may lead to an increase in compatibility between the binder resin and the repetitive
structural unit represented by the above formula (1) for the present invention. As
a result, the energy on the surface of the electrophotographic photosensitive member
may be lowered by the increased compatibility.
[0070] Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains the repetitive structural unit represented
by the above formula (1-4) preferably in an amount of 70 to 100% by number, more preferably
in an amount of 90 to 100% by number.
Re: Formula (1-5)
[0071] R
1 in the above formula (1-5) represents a hydrogen atom or a methyl group.
[0072] R
20 in the above formula (1-5) represents a single bond or an alkylene group. Examples
of the alklyene group include linear alkylene groups such as a methylene group, an
ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene
group. Of those, the methylene group, the ethylene group, the propylene group, and
the butylene group are preferable.
[0073] Rf
12 in the above formula (1-5) represents a fluoroalkyl group interrupted with oxygen.
The fluoroalkyl group interrupted with oxygen represents that at least one oxygen
atom is included in the longest bonding chain. Alternatively, a fluoroalkyl group
or a fluoroalkylene group may be present on both sides or one side of the oxygen atom.
[0075] Of those, the groups represented by the above formulae (R12-13), (R12-14), (R12-16),
and (Rf12-17) are preferable.
[0077] Of those, the repetitive structural units represented by the above formulae (1-5-2),
(1-5-4), (1-5-5), (1-5-6), (1-5-8), (1-5-11), (1-5-12), and (1-5-13) are preferable.
[0078] As described above, for obtaining an effect of preventing the blade-curling, it is
important that a polymer having the repetitive structural unit represented by the
above formula (1) for the present invention be a polymer having at least one of the
fluoroalkyl group and the fluoroalkylene group in the repetitive structural unit.
Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains repetitive structural units represented
by any one of the above formulae (1-1) to (1-6) in an amount of 70 to 100% by number.
[0079] In the case of the repetitive structural unit represented by the above formula (1-5),
the inventors of the present invention have an opinion that the effects of the present
invention can result from lowering of the energy on the surface of the electrophotographic
photosensitive member due to the fluoroalkyl group included in the repetitive structural
unit represented by the above formula (1-5). In addition, the fluoroalkyl group is
interrupted with oxygen, so the energy on the surface of the electrophotographic photosensitive
member may be lowered also by an improvement in compatibility between the binder resin
and the polymer having the repetitive structural unit represented by the above formula
(1) for the present invention.
[0080] Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains the repetitive structural unit represented
by the above formula (1-1) preferably in an amount of 70 to 100% by number, more preferably
in an amount of 90 to 100% by number.
Re: Formula (1-6)
[0081] R
1 in the above formula (1-6) represents a hydrogen atom or a methyl group.
[0082] R
20 in the above formula (1-6) represents a single bond or an alkylene group. Examples
of the alklyene group include linear alkylene groups such as a methylene group, an
ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene
group. Of those, the methylene group, the ethylene group, the propylene group, and
the butylene group are preferable.
[0083] Rf
13 in the above formula (1-6) represents a perfluoroalkyl group with 4 to 6 carbon atoms.
[0084] Specific examples of Rf
13 in the above formula (1-6) will be represented below.
[0085] Of those, groups represented by the above formulae (Rf13-1) and (Rf13-3) are preferable.
[0087] Of those, the repetitive structural units represented by the above formulae (1-6-1),
(1-6-2), (1-6-6), (1-6-7), (1-6-10), (1-6-11), (1-6-14), and (1-6-15) are preferable.
[0088] As described above, for obtaining an effect of preventing the blade-curling, it is
important that a polymer having the repetitive structural unit represented by the
above formula (1) for the present invention be a polymer having at least one of the
fluoroalkyl group and the fluoroalkylene group in the repetitive structural unit.
Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention contains repetitive structural units represented
by any one of the above formulae (1-1) to (1-6) in an amount of 70 to 100% by number.
[0089] In the case of the repetitive structural unit represented by the above formula (1-6),
the inventors of the present invention have an opinion that the effects of the present
invention can result from lowering of the energy on the surface of the electrophotographic
photosensitive member with the fluoroalkyl group and the fluorine-atom-containing
resin particles included in the repetitive structural unit represented by the above
formula (1-6). Further, the energy on the surface of the electrophotographic photosensitive
member may be lowered by an improvement in compatibility between the binder resin
and the polymer having the repetitive structural unit represented by the above formula
(1) for the present invention as the fluoroalkyl group is a perfluoroalkyl group having
4 to 6 carbon atoms.
[0090] Further, the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention is preferably formed only of the repetitive
structural unit represented by the above formula (1-6).
[0091] Further, for obtaining an effect of preventing the blade-curling, any structure with
an affinity for the binder resin of the surface layer in addition to the repetitive
structural unit represented by the above formula (1) may be included in the structure
of the polymer having the repetitive structural unit represented by the formula (1)
for the present invention.
[0092] Examples of the structure with a compatibility with the binder resin of the surface
layer include polymer units made of repetitive structural units of an alkyl acrylate
structure, an alkyl methacrylate structure, and a styrene structure. For further enhancing
the effects of the present invention, the polymer having the repetitive structural
unit represented by the above formula (1) for the present invention is preferably
a polymer having the repetitive structural unit represented by the above formula (1)
and a repetitive structural unit represented by the following formula (a):
[0093] R
101 in the above formula (a) represents a hydrogen atom or a methyl group.
[0094] Y in the above formula (a), which is a divalent organic group and arbitrary as far
as it is a divalent organic group is preferably one represented by the following formula
(c):
[0095] Y
1 and Y
2 in the above formula (c) each independently represent an alkylene group. Examples
of the alkylene group include a methylene group, an ethylene group, a propylene group,
a butylene group, a pentylene group, and a hexylene group. Of those, the methylene
group, the ethylene group, and the propylene group are preferable. The substituents
which those alkylene groups may have include alkyl groups, alkoxyl groups, hydroxyl
groups, and aryl groups. The alkyl groups include a methyl group, an ethyl group,
a propyl group, and a butyl group. Of those, the methyl group and the ethyl group
are preferable. The alkoxyl groups include a methoxy group, an ethoxy group, and a
propoxyl group. Of those, the methoxy group is preferable. The aryl groups include
a phenyl group and a naphthyl group. Of those, the phenyl group is preferable. Further,
Of those, the methyl group and the hydroxyl group are more preferable.
[0096] Z in the above formula (a) is a polymer unit and its structure is not limited as
far as Z is a polymer unit; Z is preferably a polymer unit having a repetitive structural
unit represented by the following formula (b-1) or the following formula (b-2):
[0097] R
201 in the above formula (b-1) represents an alkyl group. Examples of the alkyl group
include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group,
a hexyl group, a heptyl group, an octyl group, and a nonyl group. Of those, the methyl
group, the ethyl group, the propyl group, the butyl group, the pentyl group, and the
hexyl group are preferable.
[0098] R
202 in the above formula (b-2) represents an alkyl group. Examples of the alkyl group
include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group,
a hexyl group, a heptyl group, an octyl group, and a nonyl group. Of those, the methyl
group, the ethyl group, the propyl group, the butyl group, the pentyl group, and the
hexyl group are preferable.
[0099] The terminal end of the polymer unit represented by Z in the above formula (a) may
use a terminal-end terminating agent or may have a hydrogen atom.
[0100] The polymer having the repetitive structural unit represented by the above formula
(1) for the present invention is preferably of a structure in which both a portion
imparting a slidability derived from the fluoroalkyl group or the fluoroalkylene group
and a portion having an affinity with the binder resin of the surface layer are included
in the compound.
[0101] Any configuration of a copolymer of the repetitive structural unit represented by
the above formula (1) and the repetitive structural unit represented by the above
formula (a) may be employed. However, for allowing the fluoroalkyl portion or fluoroalkylene
portion imparting the slidability to exert their functions more effectively, a comb-type
graft structure having a repetitive structural unit represented by the above formula
(a) on any one of its side chains is more preferable.
[0102] In addition, a copolymerization ratio between the repetitive structural unit represented
by the above formula (1) and the repetitive structural unit represented by the above
formula (a) is preferably 99:1 to 20:80, more preferably 95:5 to 30:70 in molar ratio
for obtaining the effects of the present invention. The copolymerization ratio can
be controlled by a molar ratio at the time of polymerizing a compound represented
by the above formula (3) corresponding to the repetitive structural unit represented
by the above formula (1) and a compound represented by the above formula (d) corresponding
to the repetitive structural unit represented by the above formula (a).
[0103] The molecular weight of the polymer having the repetitive structural unit represented
by the above formula (1) for the present invention is preferably 1,000 to 100,000,
more preferably in 5,000 to 50,000 in weight average molecular weight.
[0104] The polymer for the present invention, having the repetitive structural units each
represented by the formula (1) can be synthesized by polymerization of compounds each
represented by the following formula (3):
(where R
1 represents a hydrogen atom or a methyl group, R
2 represents a single bond or a divalent group, and Rf
1 represents a monovalent group having at least one of a fluoroalkyl group and a fluoroalkylene
group.) Note that 70 to 100% by number of the compounds each represented by the above
formula (3) should include compounds each represented by any one of the following
formulae (3-1) to (3-6):
(where R
1 represents a hydrogen atom or a methyl group, R
20 represents a single bond or an alkylene group, R
21 represents an alkylene group having a branched structure with a carbon-carbon bond,
R
22 represents a -R
21- group or a -O-R
21- group, R
23 represents a -Ar-group, a -O-Ar- group, or a -O-Ar-R- group (where Ar represents
an arylene group and R represents an alkylene group.), Rf
10 represents a monovalent group having at least a fluoroalkyl group, Rf
11 represents a fluoroalkyl group having a branched structure with a carbon-carbon bond,
Rf
12 represents a fluoroalkyl group interrupted with oxygen, and Rf
13 represents a perfluoroalkyl group having 4 to 6 carbon atoms.)
Re: Formula (3)
[0105] R
1 in the above formula (3) represents a hydrogen atom or a methyl group.
[0106] R
2 in the above formula (3) represents a single bond or a divalent group. The divalent
group may be preferably one having at least an alkylene group or an arylene group
in its structure. Examples of the alklyene group include: linear alkylene groups such
as a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene
group, and a hexylene group; and branched alkylene groups such as an isopropylene
group and an isobutylene group. Of those, the methylene group, the ethylene group,
the propylene group, and the butylene group are preferable. Examples of the arylene
group include a phenylene group, a naphthylene group, and a biphenylene group. Of
those, the phenylene group is preferable.
[0107] In the above formula (3), Rf
1 represents a monovalent group having at least one of a fluoroalkyl group and a fluoroalkylene
group. Examples of the fluoroalkyl group include the following:
[0108] Examples of the fluoroalkylene group include the following:
Re: Formula (3-1)
[0109] R
1 in the above formula (3-1) represents a hydrogen atom or a methyl group.
[0110] R
20 in the above formula (3-1) represents a single bond or an alkylene group. Examples
of the alklyene group include linear alkylene groups such as a methylene group, an
ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene
group. Of those, the methylene group, the ethylene group, the propylene group, and
the butylene group are preferable.
[0111] Rf
11 in the above formula (3-1) represents a fluoroalkyl group having a branched structure
with a carbon-carbon bond. The branched structure with a carbon-carbon bond represents
a structure in which the longest bonding chain and side chains thereof are bonded
with each other by carbon-carbon bonds. In addition, part or the whole of the longest
bonding chain and/or the side chains may be substituted with fluorine.
[0112] Specific examples of Rf
11 in the above formula (3-1) include groups represented by the above formulae (Rf11-1)
to (Rf11-18).
[0114] Of those, compounds represented by the above formulae (3-1-3), (3-1-4), (3-1-6),
(3-1-7), (3-1-10), (3-1-11), (3-1-13), and (3-1-14) are preferable.
Re: Formula (3-2)
[0115] R
1 in the above formula (3-2) represents a hydrogen atom or a methyl group.
[0116] R
21 in the above formula (3-2) represents an alkylene group having a branched structure
with a carbon-carbon bond. The branched structure with a carbon-carbon bond represents
a structure in which the longest bonding chain and the side chains thereof are bonded
by carbon-carbon bonds. The longest bonding chain is preferably formed of 2 to 6 carbon
atoms. In addition, each of the side chains may be an alkyl group, a fluoroalkyl group,
or the like. The alkyl group may be a methyl group, an ethyl group, a propyl group,
or a butyl group. Of those, the methyl group and the ethyl group are preferable. The
fluoroalkyl group may be, for example, any of the groups represented by the above
formulae (CF-1) to (CF-3). Of those, the group represented by the above formula (CF-1)
is preferable.
[0117] Rf
10 in the above formula (3-2) represents a monovalent group with at least a fluoroalkyl
group. Examples of the fluoroalkyl group include the groups represented by the above
formulae (CF-1) to (CF-3). In addition, Rf
10 is not limited to a linear structure but may be of a branched structure. Alternatively,
Rf
10 may be a fluoroalkyl group interrupted with an oxygen atom.
[0118] Specific examples of Rf
10 in the above formula (3-2) include groups represented by the above formulae (Rf10-1)
to (R10-36).
[0120] Of those, compounds represented by the above formulae (3-2-1) and (3-2-2) are preferable.
Re: Formula (3-3)
[0121] R
1 in the above formula (3-3) represents a hydrogen atom or a methyl group.
[0122] R
22 in the above formula (3-3) represents a -R
21-group or a -O-R
21- group. To be specific, the -R
21-group represents an alkylene group having a branched structure with a carbon-carbon
bond. The branched structure with a carbon-carbon bond represents a structure in which
the longest bonding chain and the side chains thereof are bonded by carbon-carbon
bonds. The longest bonding chain is preferably formed of 2 to 6 carbon atoms. In addition,
each of the side chains may be an alkyl group or a fluoroalkyl group. The alkyl group
may be, for example, a methyl group, an ethyl group, a propyl group, or a butyl group.
Of those, the methyl group and the ethyl group are preferable. The fluoroalkyl group
may be, for example, a group represented by any of the above formulae (CF-1) to (CF-3).
Of those, the group represented by the above formula (CF-1) is preferable. Further,
the -OR
21- group represents a structure in which the alkylene group having a branched structure
with a carbon-carbon bond is bonded to Rf
10 through an oxygen atom.
[0123] Rf
10 in the above formula (3-3) represents a monovalent group with at least a fluoroalkyl
group. The fluoroalkyl group may be, for example, a group represented by any of the
above formulae (CF-1) to (CF-3). Further, Rf
10 is not limited to a linear structure but may be of a branched structure. Alternatively,
Rf
10 may be a fluoroalkyl group interrupted with an oxygen atom.
[0124] Specific examples of Rf
10 in the above formula (3-3) include groups represented by the above formulae (Rf10-1)
to (R10-36).
[0126] Of those, compounds represented by the above formulae (3-3-1), (3-3-2), (3-3-3),
(3-3-4), (3-3-6), (3-3-9), (3-3-10), (3-3-11), (3-3-12), and (3-3-14) are preferable.
Re: Formula (3-4)
[0127] R
1 in the above formula (3-4) represents a hydrogen atom or a methyl group.
[0128] R
23 in the above formula (3-4) represent a -Ar-group, a -O-Ar- group, or a -O-Ar-R- group
(Ar represents an arylene group and R represents an alkylene group). Examples of the
arylene group of Ar include a phenylene group, a naphthylene group, and a biphenylene
group. Of those, the phenylene group is preferable. Examples of the alkylene group
of R include: linear alkylene groups such as a methylene group, an ethylene group,
a propylene group, a butylene group, a pentylene group, and a hexylene group; and
branched alkylene groups such as an isopropylene group and an isobutylene group. Of
those, the methylene group, the ethylene group, the propylene group, and the butylene
group are preferable. The -O-Ar- group or the -O-Ar-R- group represents a structure
to be bonded to Rf
10 through an oxygen atom.
[0129] Rf
10 in the above formula (3-4) represents a monovalent group with at least a fluoroalkyl
group. The fluoroalkyl group may be, for example, a group represented by any of the
above formulae (CF-1) to (CF-3). Further, Rf
10 is not limited to a linear structure but may be of a branched structure. Alternatively,
Rf
10 may be a fluoroalkyl group interrupted with an oxygen atom.
[0130] Specific examples of Rf
10 in the above formula (3-4 include those represented by the above formulae (Rf10-1)
to (R10-36).
[0132] Of those, compounds represented by the above formulae (3-4-1), (3-4-6), (3-4-7),
(3-4-8), (3-4-10), (3-4-15), (3-4-16), and (3-4-17) are preferable.
Re: Formula (3-5)
[0133] R
1 in the above formula (3-5) represents a hydrogen atom or a methyl group.
[0134] R
20 in the above formula (3-5) represents a single bond or an alkylene group. Examples
of the alklyene group include linear alkylene groups such as a methylene group, an
ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene
group. Of those, the methylene group, the ethylene group, the propylene group, and
the butylene group are preferable.
[0135] Rf
12 in the above formula (3-5) represents a fluoroalkyl group interrupted with oxygen.
The fluoroalkyl group interrupted with oxygen represents that at least one oxygen
atom is included in the longest bonding chain. Alternatively, a fluoroalkyl group
or a fluoroalkylene group may be present on both sides or one side of the oxygen atom.
[0136] Specific examples of Rf
12 in the above formula (3-5) include groups represented by the above formulae (Rf12-1)
to (R12-17).
[0138] Of those, compounds represented by the above formulae (3-5-2), (3-5-4), (3-5-5),
(3-5-6), (3-5-8), (3-5-11), (3-5-12), and (3-5-13) are preferable.
Re: Formula (3-6)
[0139] R
1 in the above formula (3-6) represents a hydrogen atom or a methyl group.
[0140] R
20 in the above formula (3-6) represents a single bond or an alkylene group. Examples
of the alklyene group include: linear alkylene groups such as a methylene group, an
ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene
group. Of those, the methylene group, the ethylene group, the propylene group, and
the butylene group are preferable.
[0141] Rf
13 in the above formula (3-6) represents a perfluoroalkyl group with 4 to 6 carbon atoms.
[0142] Specific examples of Rf
13 in the above formula (3-6) include groups represented by the above formulae (Rf13-1)
to (Rf13-3).
[0144] Of those, compounds represented by the above formulae (3-6-1), (3-6-2), (3-6-6),
(3-6-7), (3-6-10), (3-6-11), (3-6-14), and (3-6-15) are preferable.
[0145] The compound represented by the above formula (3) can be produced by a combination
of production methods well known in the art.
[0146] A method of producing a compound represented by the above formula (3) will be exemplified.
[0147] According to the method disclosed in Japanese Patent Application Laid-Open No.
2005-054020, an iodinated material of a fluoroalkyl group (Rf
1 group) is used as a starting material, whereby a compound represented by the above
formula (3) where R
1 is H, and R
2 is CH
2-CH
2 is obtained.
[0148] Alternatively, any compound represented by the above formula (3) can be obtained
with reference to any of the other production methods disclosed in, for example, Japanese
Patent Application Laid-Open No.
2001-302571 and Japanese Patent Application Laid-Open No.
2001-199953.
Rf
1-I + H
2C=CH
2 → Rf
1-CH
2-CH
2-I
Rf
1-CH
2-CH
2-I + H
2O → Rf
1-CH
2-CH
2-OH
(In the above formula, R
1 represents R
1 in the formula (3) and Rf
1 represents Rf
1 in the formula (3)).
[0149] Further, the compound represented by the above formula (3-2) has a plurality of ester
structures. Therefore, on this account, a by-product material or a residual compound
remaining after the polymerization of compounds represented by the above formula (3-2)
can be easily removed by washing the resulting polymer with water or alcohol. As a
result, the compound having the repetitive structural unit represented by the above
formula (1-2) can be obtained at high purity. The acquisition of the compound at high
purity may also contribute to the maintenance of electrophotographic properties in
a favorable condition.
[0150] The compound having the repetitive structural units each represented by the above
formula (a) is synthesized by the polymerization of compounds each represented by
the following formula (d):
(where R
101 represents a hydrogen atom or a methyl group, Y represents a divalent organic group,
and Z represents a polymer unit).
[0151] R
101 in the above formula (d) represents a hydrogen atom or a methyl group.
[0152] Y in the above formula (d), which is a divalent organic group and arbitrary as far
as it is a divalent organic group, is preferably one represented by the following
formula (c):
[0153] Y
1 and Y
2 in the above formula (c) each independently represent an alkylene group. Examples
of the alkylene group include a methylene group, an ethylene group, a propylene group,
a butylene group, a pentylene group, and a hexylene group. Of those, the methylene
group, the ethylene group, and the propylene group are preferable. The substituents
which those alkylene groups may have include alkyl groups, alkoxyl groups, hydroxyl
groups, and aryl groups. The alkyl groups include a methyl group, an ethyl group,
a propyl group, and a butyl group. Of those, the methyl group and the ethyl group
are preferable. The alkoxyl groups include a methoxy group, an ethoxy group, and a
propoxyl group. Of those, the methoxy group is preferable. The aryl groups include
a phenyl group and a naphthyl group. Of those, the phenyl group is preferable. Further,
of those, the methyl group and the hydroxyl group are more preferable.
[0154] Z in the above formula (d) is a polymer unit and its structure is not limited as
far as Z is a polymer unit; Z is preferably a polymer unit having a repetitive structural
unit represented by the following formula (b-1) or the following formula (b-2):
[0155] R
201 in the above formula (b-1) represents an alkyl group. Examples of the alkyl group
include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group,
a hexyl group, a heptyl group, an octyl group, and a nonyl group. Of those, the methyl
group, the ethyl group, the propyl group, the butyl group, the pentyl group, and the
hexyl group are preferable.
[0156] R
202 in the above formula (b-2) represents an alkyl group. Examples of the alkyl group
include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group,
a hexyl group, a heptyl group, an octyl group, and a nonyl group. Of those, the methyl
group, the ethyl group, the propyl group, the butyl group, the pentyl group, and the
hexyl group are preferable.
[0157] The terminal end of the polymer unit represented by Z in the above formula (d) may
use a terminal-end terminating agent or may have a hydrogen atom.
[0158] The polymer having the repetitive structural unit represented by the above formula
(1) for the present invention can be produced by the polymerization of compounds represented
by the above formula (3). Further, the polymer having both the repetitive structural
unit represented by the above formula (1) and the repetitive structural unit represented
by the above formula (a) can be produced by copolymerizing the compound represented
by the above formula (3) with the compound represented by the above formula (d) according
to the procedures disclosed in, for example, Japanese Patent Application Laid-Open
No.
58-164656.
[0159] Hereinafter, an example of the method of producing the compound represented by the
above formula (d) will be described. In the following formula, there is exemplified
a compound with the structure represented by the above formula (d) where R
101 is a methyl group, Y is a divalent organic group having the structure represented
by the above formula (c), and Z is a polymer unit represented by the above formula
(b-2). Further, in the above formula (c), Y
1 is a methylene group and Y
2 is a propylene group having a hydroxyl group.
(Step 1)
[0160] To an alkyl acrylate monomer or an alkyl methacrylate monomer, which can be provided
as a raw material for a polymer having a repetitive structural unit represented by
the above formula (b-1) or the above formula (b-2), is added a chain transfer agent
in an amount of several mass% in monomer ratio, whereby the polymerization of the
monomer is carried out. Consequently, an alkyl acrylate polymer or an alkyl methacrylate
polymer having a terminal end coupled with the chain transfer agent is obtained. The
chain transfer agent may be any of carboxylic acids with a mercapto group such as
thioglycolic acid, 3-mercapto propionic acid, 2-mercapto propionic acid, and 4-mercapto-n-butanoic
acid.
(Step 2)
[0161] The alkyl acrylate polymer or alkyl methacrylate polymer is reacted with a monomer
(in the following formula, glycidyl methacrylate) that provides a functional group
for bonding to the polymer and forms a main chain in the subsequent reaction with
the functional group to the functional group being reacted with each other. Consequently,
a compound represented by the above formula (d) is obtained. The above glycidyl methacrylate
has a polymerizable functional group and a functional group (epoxy moiety) which can
bind to a carboxyl group in the chain transfer agent. The monomer is not limited to
glycidyl methacrylate as far as it is a monomer of similar functional-group configuration.
(R
202 in the formula represents an alkyl group)
[0162] The copolymer of the repetitive structural unit represented by the above formula
(1) and the repetitive structural unit represented by the above formula (a) can be
produced according to the procedure disclosed in Japanese Patent Application Laid-Open
No.
58-164656 using the compound represented by the above formula (3) and the compound represented
by the above formula (d). In this way, a compound having a portion with a fluoroalkyl
group or a fluoroalkylene group contributing to an improvement in slidability between
the surface of an electrophotographic photosensitive member and a cleaning blade and
a portion with an affinity for a binder resin in the surface layer can be obtained.
[0163] The polymer having a repetitive structural unit represented by the above formula
(1) for the present invention has insufficient functions as a photoconductive substance
and a binder resin of the surface layer. Thus, the polymer as a constituent component
of the surface layer is preferably used in as small an amount as possible. In addition,
the blade-curling may occur at high frequency at an early stage immediately after
the setting of an electrophotographic apparatus, or before the accumulation of transfer
residual toner on the contact boundary surface between the cleaning blade and the
electrophotographic photosensitive member. When the material of the cleaning blade
is an elastic rubber material, there is a tendency of further increasing the occurrence
frequency of blade-curling under a high-temperature, high-humidity environment. Therefore,
it is preferable to allow a sufficient amount of a compound having a repetitive unit
represented by the above formula (1) for the present invention to be located adjacent
to the surface of the surface layer of the electrophotographic photosensitive member.
From such a viewpoint, a polymer having a repetitive unit represented by the above
formula (1) for the present invention with a portion having a fluoroalkyl group or
a fluoroalkylene group, which is movable to the surface of the surface layer of the
electrophotographic photosensitive member, is preferably incorporated in the surface
layer.
[0164] The structure of the fluoroalkyl group of the repetitive structural unit represented
by the above formula (1-1) is not a linear chain but a branched structure. In the
case of the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention, which includes the repetitive structural unit
represented by the above formula (1-1), micelles of the polymer having the repetitive
structural unit represented by the above formula (1) for the present invention are
hardly formed in a solution or a dispersion liquid. Therefore, the liquid composition
in the solution or the dispersion liquid can be uniformed. In addition, a small amount
of ionic impurities is hardly mixed, so that this fact may contribute to improvements
in characteristics and keep electrophotographic properties in a favorable condition.
[0165] The structure of the repetitive structural unit represented by the above formula
(1-2) is a branched structure. In the case of the polymer having the repetitive structural
unit represented by the above formula (1) for the present invention, which includes
the repetitive structural unit represented by the above formula (1-2), micelles of
the compound having the repetitive structural unit represented by the above formula
(1) are hardly formed in a solution or a dispersion liquid. Therefore, the liquid
composition in the solution or the dispersion liquid can be uniformed. In addition,
a small amount of ionic impurities is hardly mixed, so that this fact may contribute
to improvements in characteristics and keep electrophotographic properties in a favorable
condition.
[0166] The structure of the repetitive structural unit represented by the above formula
(1-3) is a branched structure. In the case of the polymer having the repetitive structural
unit represented by the above formula (1) for the present invention, which includes
the repetitive structural unit represented by the above formula (1-3), micelles of
the compound having the repetitive structural unit represented by the above formula
(1) are hardly formed in a solution or dispersion liquid. Therefore, the liquid composition
in the solution or the dispersion liquid can be uniformed. In addition, a small amount
of ionic impurities is hardly mixed, so that this fact may contribute to improvements
in characteristics and keep electrophotographic properties in a favorable condition.
[0167] The structure of the repetitive structural unit represented by the above formula
(1-4) is a structure containing an arylene group. In the case of the polymer having
the repetitive structural unit represented by the above formula (1) for the present
invention, which includes the repetitive structural unit represented by the above
formula (1-4), micelles of the compound having the repetitive structural unit represented
by the above formula (1) are hardly formed in a solution or dispersion liquid. Therefore,
the liquid composition in the solution or the dispersion liquid can be uniformed.
In addition, a small amount of ionic impurities is hardly mixed, so that this fact
may contribute to improvements in characteristics and keep electrophotographic properties
in a favorable condition.
[0168] The structure of the repetitive structural unit represented by the above formula
(1-5) is a structure containing a fluoroalkyl group interrupted with oxygen. In the
case of the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention, which includes the repetitive structural unit
represented by the above formula (1-5), micelles of the compound having the repetitive
structural unit represented by the above formula (1) are hardly formed in a solution
or a dispersion liquid. Therefore, the liquid composition in the solution or the dispersion
liquid can be uniformed. In addition, a small amount of ionic impurities is hardly
mixed, so that this fact may contribute to improvements in characteristics and keep
electrophotographic properties in a favorable condition.
[0169] The structure of the repetitive structural unit represented by the above formula
(1-6) is a structure containing a perfluoroalkyl group with 4 to 6 carbon atoms. In
the case of the polymer having the repetitive structural unit represented by the above
formula (1) for the present invention, which includes the repetitive structural unit
represented by the above formula (1-6), micelles of the compound having the repetitive
structural unit represented by the above formula (1) are hardly formed in a solution
or a dispersion liquid. Therefore, the liquid composition in the solution or the dispersion
liquid can be uniformed. In addition, a small amount of ionic impurities is hardly
mixed, so that this fact may contribute to improvements in characteristics and keep
electrophotographic properties in a favorable condition.
[0170] Next, the configuration of the electrophotographic photosensitive member of the present
invention will be described.
[0171] As an example of the electrophotographic photosensitive member of the present invention,
as shown in FIG. 1A to FIG. 1E, an electrophotographic photosensitive member having
an intermediate layer 103 and a photosensitive layer 104 on a support 101 in this
order can be exemplified (see FIG. 1A).
[0172] In addition, for example, between the support 101 and the intermediate layer 103
may be provided a conductive layer 102 which is formed by dispersing conductive particles
in a resin and whose volume resistance is made smaller and thickness is made greater.
The layer 102 can be used as a layer for covering defects in the surface of the conductive
support 101 or the non-conductive support 101 (for example, resin support) (see FIG.
1B).
[0173] A photosensitive layer 104 may be a monolayer type photosensitive layer 104 containing
a charge-transporting substance and a charge-generating substance in the same layer
(see FIG. 1A). Further, the photosensitive layer 104 may be a multilayer type (separate
function type) photosensitive layer composed of a charge-generating layer 1041 containing
a charge-generating substance and a charge-transporting layer 1042 containing a charge-transporting
substance separately. The multilayer type photosensitive layer is preferred in view
of electrophotographic properties. In the case of a monolayer type photosensitive
layer, the surface layer of the present invention is the photosensitive layer 104.
In addition, there are two kinds of the multilayer type photosensitive layer. One
is a normal-layer type photosensitive layer in which the charge-generating layer 1041
and the charge-transporting layer 1042 are laminated on the support 101 in the named
order from the support 101 (see FIG. 1C). The other is a reverse-layer type photosensitive
layer in which the charge-transporting layer 1042 and the charge-generating layer
1041 are laminated on the support 101 in the order from the support 101 (see FIG.
1D). From a viewpoint of electrophotographic properties, the normal-type photosensitive
layer is preferred. Of the multilayer type photosensitive layers, in the case of the
normal-layer type photosensitive layer, the surface layer of the electrophotographic
photosensitive member is a charge-transporting layer. In the case of the reverse-layer
type photosensitive layer, the surface layer is a charge-generating layer (but when
a protective layer is not provided).
[0174] In addition, a protective layer 105 may be formed on the photosensitive layer 104
(charge-generating layer 1041 and charge-transporting layer 1042) (see FIG. 1E). In
the case where the electrophotographic photosensitive member has the protective layer
105, the surface layer of the electrophotographic photosensitive member is the protective
layer 105.
[0175] The support 101 is preferably conductive (conductive support) and may be one made
of a metal such as aluminum, an aluminum alloy, or stainless steel. In the case of
aluminum or an aluminum alloy, the support 101 used may be an ED tube or an EI tube
or one obtained by subjecting the ED tube or the EI tube to cutting, electrolytic
complex polish (electrolysis with an electrode having an electrolytic action and an
electrolytic solution, and polishing with a whetstone having polishing actions), or
a wet- or dry-honing process. Also, the above metal-made support having a layer formed
by film-formation with vacuum deposition of aluminum, an aluminum alloy, or an indium
oxide-tin oxide alloy may be used. In addition, a resin-made support (polyethylene
terephthalate, polybutylene terephthalate, a phenol resin, polypropylene, or a polystyrene
resin) having a layer formed by film-formation with vacuum deposition may be used.
Alternatively, a support prepared by impregnating conductive particles such as carbon
black, tin oxide particles, titanium oxide particles, and silver particles into a
resin or paper may be used, or a plastic having a conductive binder resin may be used.
[0176] As to the volume resistivity of the support, when the surface of the support is a
layer provided for imparting the conductivity to the support, the volume resistibity
of the layer is preferably 1 x 10
10 Ω·cm or less, more preferably 1 x 10
6 Ω·cm or less.
[0177] A conductive layer may be formed on the support for the purpose of covering defects
in the surface of the support. The conductive layer is a layer formed by applying
a coating solution prepared by dispersing conductive particles in a suitable binder
resin on the support.
[0178] Such conductive powders include: carbon black; acetylene black; metal powders made
of, for example, aluminum, nickel, iron, nichrome, copper, zinc, and silver; and metal
oxide powders made of, for example, conductive tin oxide and ITO.
[0179] In addition, a binder resin simultaneously used with the conductive powders may be
any of the following thermoplastic resins, thermosetting resins, and photocurable
resins.
[0180] Polystyrene, a styrene-acrylonitrile copolymer, a styrene-butadiene copolymer, a
styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, a vinyl chloride-vinyl
acetate copolymer, polyvinyl acetate, polyvinylidene chloride, a polyallylate resin,
a phenoxy resin, polycarbonate, a cellulose acetate resin, an ethylcellulose resin,
polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, an
acryl resin, a silicone resin, an epoxy resin, a melamine resin, a urethane resin,
a phenol resin, and an alkyd resin.
[0181] The conductive layer can be formed by dispersing or dissolving the above conductive
powders and the binder resin into an organic solvent, followed by coating. Examples
of the organic solvent include: ether-based solvents (e.g., tetrahydrofuran, ethylene
glycol dimethyl ether); alcohol-based solvents (e.g., methanol); ketone-based solvents
(e.g., methyl ethyl ketone); and aromatic hydrocarbon solvents (e.g., toluene).
[0182] The film thickness of the conductive layer is preferably 5 to 40 µm, more preferably
10 to 30 µm.
[0183] An intermediate layer having a barrier function may be provided on the support or
the conductive layer.
[0184] The intermediate layer can be formed in such a manner that a hardening resin is applied
and then hardened to form a resin layer. Alternatively, the intermediate layer can
be formed in such a manner that an intermediate-layer coating solution containing
a binder resin is applied on a conductive layer and then dried to form such a layer.
[0185] Examples of the binder resin in the intermediate layer include the following resins:
[0186] Water-soluble resins including polyvinyl alcohol, polyvinyl methyl ether, polyacrylic
acids, methylcellulose, ethylcellulose, polyglutamic acid, and casein; a polyamide
resin, a polyimide resin, a polyamide imide resin, a polyamic acid resin, a melamine
resin, an epoxy resin, a polyurethane resin, and a polyglutamate resin.
[0187] For effectively expressing the electric barrier property of the intermediate layer
and from the viewpoint of coating characteristics, adhesiveness, solvent resistance,
and electrical resistance, the binder resin in the intermediate layer is preferably
a thermoplastic resin. To be specific, a thermoplastic polyamide resin is preferable.
The polyamide resin is preferably copolymer nylon with low crystallity or non-crystalline
copolymer nylon which can be applied in a solution state.
[0188] The film thickness of the intermediate layer is preferably 0.1 to 2.0 µm.
[0189] In addition, semiconductive particles may be dispersed in or an electron-transporting
substance (electron-accepting substance such as an acceptor) may be added to the intermediate
layer to prevent the flow of charges (carriers) from being disrupted in the intermediate
layer.
[0190] A photosensitive layer is formed on the support, the conductive layer, or the intermediate
layer.
[0191] Examples of the charge-generating substance used in the electrophotographic photosensitive
member of the present invention include the following: Azo pigments such as monoazo,
disazo, and tris azo; phthalocyanine pigments such as metallophthalocyanine and metalloid
phthalocyanine; indigo pigments such as indigo and thioindigo; perylene pigments such
as perylene acid anhydride and perylene acid imide; polycyclic quinone pigments such
as anthraquinone and pyrene quinone; squalelium coloring matter, a pyrylium salt,
and a thiapyrylium salt, and a triphenylmethane dye; inorganic substances such as
selenium, selenium-tellurium, and amorphous silicon; and quinacridone pigments, azulenium
salt pigments, a cyanine dye, a xanthene coloring matter, quinonimine coloring matter,
and styryl coloring matter.
[0192] Any one of those charge-generating substances may be used alone, or two or more of
them may be used in combination. Of those, in particular, the metallophthalocyanines,
such as oxytitanium phthalocyanine, hydroxygallium phthalocyanine, and chlorogallium
phthalocyanine are preferable because of their high sensitivities.
[0193] When the photosensitive layer is a multilayer type photosensitive layer, the binder
resin used in the charge-generating layer may be, for example, any of the following:
a polycarbonate resin, a polyester resin, a polyallylate resin, a butyral resin, a
polystyrene resin, a polyvinyl acetal resin, a diallylphthalate resin, an acryl resin,
a methacryl resin, a vinyl acetate resin, a phenol resin, a silicone resin, a polysulfone
resin, a styrene-butadiene copolymer resin, an alkyd resin, an epoxy resin, a urea
resin, and a vinyl chloride-vinyl acetate copolymer resin.
[0194] Of those, the butyral resin is preferable. They may be independently used. Alternatively,
two or more kinds of them may be used as a mixture or a copolymer.
[0195] The charge-generating layer can be formed by applying a charge-generating layer coating
solution, which is prepared by dispersing a charge-generating substance into a solvent
together with a binder resin, and then drying the coating solution. For example, a
dispersion method may be one using a homogenizer, an ultrasonic wave, a ball mill,
a sand mill, an attritor, or a roll mill. A ratio between the charge-generating substance
and the binder resin is preferably in the range of 10:1 to 1:10 (mass ratio), more
preferably in the range of 3:1 to 1:1 (mass ratio).
[0196] The solvent used in the charge-generating layer coating solution is selected on the
basis of a binder resin to be used, and the solubility and dispersion stability of
the charge-generating substance. The organic solvent may be an alcohol-based solvent,
a sulfoxide-based solvent, a ketone-based solvent, an ether-based solvent, an ester-based
solvent, or an aromatic hydrocarbon solvent.
[0197] The film thickness of the charge-generating layer is preferably 5 µm or less, more
preferably 0.1 to 2 µm.
[0198] Further, the charge-generating layer may be added with any of various sensitizers,
antioxidants, UV absorbents, plasticizers, and so on if required. An electron-transporting
substance (electron-accepting substance such as an acceptor) may be added to the charge-generating
layer to prevent the flow of charge (carriers) from being disrupted in the charge-generating
layer.
[0199] Examples of the charge-transporting substance to be used in the electrophotographic
photosensitive member of the present invention include a triarylamine compound, a
hydrazone compound, a styryl compound, a stilbene compound, a pyrazoline compound,
an oxazole compound, a thiazole compound, and a triallylmethane compound. One kind
of those charge-transporting substances may be used alone, or two or more kinds of
them may be used in combination.
[0200] When the photosensitive layer is a multilayer type photosensitive layer, the following
may be given as examples of the binder resin to be used in the charge-transporting
layer: an acryl resin, a styrene resin, a polyester resin, a polycarbonate resin,
a polyallylate resin, a polysulfone resin, a polyphenylene oxide resin, an epoxy resin,
a polyurethane resin, an alkyd resin, and an unsaturated resin.
[0201] Of those, in particular, a polymethyl methacrylate resin, a polystyrene resin, a
styrene-acrylonitrile copolymer resin, a polycarbonate resin, a polyallylate resin,
or a diallyl phthalate resin is preferable. One kind of those resins can be used alone,
or two or more kinds of them can be used as a mixture or a copolymer.
[0202] The charge-transporting layer can be formed by applying a charge-transporting layer
coating solution obtained by dissolving a charge-transporting substance and a binder
resin into a solvent and then drying. A ratio between the charge-transporting substance
and the binder resin is preferably in the range of 2:1 to 1:2 (mass ratio).
[0203] When the charge-transporting layer is a surface layer, a polymer having a repetitive
structural unit represented by the above formula (1) for the present invention is
included in a charge-transporting layer coating solution (surface-layer coating solution).
The content of the polymer is preferably 0.01 to 20.0 mass%, more preferably 0.1 to
5.0 mass% with respect to the total amount of the charge-transporting substance and
the binder resin.
[0204] Examples of the solvent used for the charge-transporting layer coating solution include:
ketone-based solvents such as acetone and methyl ethyl ketone; ester-based solvents
such as methyl acetate and ethyl acetate; ether-based solvents such as tetrahydrofuran,
dioxolane, dimethoxymethane, and dimethoxyethane; and aromatic hydrocarbon solvents
such as toluene and xylene.
[0205] Any of those solvents may be used alone, or two or more of them may be used as a
mixture. Of those solvents, it is preferable to use any of the ether-based solvents
and the aromatic hydrocarbon solvents from the viewpoint of resin solubility.
[0206] The charge-transporting layer has a film thickness of preferably 5 to 40 µm, or more
preferably 10 to 30 µm.
[0207] In addition, the charge-transporting layer may be added with, for example, an antioxidant,
a UV absorber, or a plasticizer if required.
[0208] When the photosensitive layer is a monolayer type photosensitive layer and provided
as the surface layer of an electrophotographic photosensitive member, in the monolayer
type photosensitive layer, a polymer having the repetitive structural unit represented
by the above formula (1) for the present invention is added to the above charge-generating
substance, the above charge-transporting substance, the above binder resin, and the
above solvent. A coating solution for the monolayer type photosensitive layer thus
obtained may be applied and dried to form the photosensitive layer of the electrophotographic
photosensitive member (monolayer type photosensitive layer).
[0209] Further, a protective layer intended to protect the photosensitive layer may be formed
on the photosensitive layer. The protective layer can be formed by applying a coating
solution for protective layer, which is prepared by dissolving various kinds of the
binder resins in a solvent as described above, and then drying.
[0210] When the surface layer of the electrophotographic photosensitive member is a protective
layer, a polymer having the repetitive structural unit represented by the above formula
(1) for the present invention is contained in the protective layer just as in the
case where the above charge-transporting layer is the surface layer. Consequently,
the surface layer of the electrophotographic photosensitive member of the present
invention can be formed.
[0211] The film thickness of the protective layer is preferably 0.5 to 10 µm, more preferably
1 to 5 µm.
[0212] For the application of each of the coating solutions corresponding to the respective
layers, any of the application methods can be employed. Such methods include dip coating,
spraying coating, spinner coating, roller coating, Mayer bar coating, blade coating,
and ring coating.
[0213] FIG. 2 illustrates an exemplified schematic configuration of an electrophotographic
apparatus equipped with a process cartridge of the present invention.
[0214] In FIG. 2, a cylindrical electrophotographic photosensitive member 1 can be driven
to rotate around an axis 2 in the direction indicated by the arrow at a predetermined
peripheral speed.
[0215] The surface of the electrophotographic photosensitive member 1 to rotate is uniformly
charged in positive or negative at predetermined potential by a charging unit (primary
charging unit: for example, a charging roller) 3. Subsequently, the surface of the
electrophotographic photosensitive member 1 receives exposure light (image exposure
light) 4 emitted from an exposure unit (not shown) such as a slit exposure or a laser-beam
scanning exposure. In this way, electrostatic latent images corresponding to the respective
images of interest are sequentially formed on the surface of the electrophotographic
photosensitive member 1.
[0216] The electrostatic latent images formed on the surface of the electrophotographic
photosensitive member 1 are converted into toner images by development with toner
contained in a developer of a developing unit 5. Subsequently, the toner images being
formed and held on the surface of the electrophotographic photosensitive member 1
are sequentially transferred to a transfer material (such as paper) P by a transfer
bias from a transfer unit (e.g., transfer roller) 6. The transfer material P is fed
to a portion (contact part) between the electrophotographic photosensitive member
1 and the transfer unit 6 in synchronization with the rotation of the electrophotographic
photosensitive member 1.
[0217] The transfer material P which has received the transfer of the toner images is separated
from the surface of the electrophotographic photosensitive member 1 and then introduced
to a fixing unit 8. The transfer material P is subjected to an image fixation and
then printed as an image-formed product (print or copy) out of the apparatus.
[0218] The surface of the electrophotographic photosensitive member 1 after the transfer
of the toner images is cleaned by removal of the remaining developer (toner) after
the transfer by a cleaning unit (e.g., cleaning blade) 7. Further, the surface of
the electrophotographic photosensitive member 1 is subjected to a neutralization process
with pre-exposure light (not shown) from a pre-exposure unit (not shown) and then
repeatedly used in image formation. As shown in FIG. 2, furthermore, when the charging
unit 3 is a contact-charging unit using a charging roller, the pre-exposure is not
always required.
[0219] Of the structural components including the electrophotographic photosensitive member
1, the charging unit 3, the developing unit 5, and the cleaning unit 7 as described
above, two or more of them may be housed in a container and then integrally combined
as a process cartridge. In addition, the process cartridge may be designed so as to
be detachably mounted on the main body of an electrophotographic apparatus such as
a copying machine or a laser beam printer. In FIG. 2, the electrophotographic photosensitive
member 1, the charging unit 3, the developing unit 5, and the cleaning unit 7 are
integrally supported and placed in a cartridge, thereby forming a process cartridge
9. The process cartridge 9 is detachably mounted on the main body of the electrophotographic
apparatus using a guide unit 10 such as a rail of the main body of the electrophotographic
apparatus.
(Examples)
[0220] Hereinafter, the present invention will be described in detail with reference to
specific examples. However, the present invention is not limited to these examples.
In addition, part(s) means mass part(s) and % means mass% in the examples.
(Synthesis Example (A-1): Synthesis of compound represented by the above formula (3-1-3))
[0221] An iodinated material (0.5 part) represented by the following formula (A-e-1):
and ion-exchanged water (20 parts) were charged to a deaerated autoclave, followed
by heating up to 300°C to carry out a conversion reaction of iodine to a hydroxyl
group at a gauge pressure of 9.2 MPa for 4 hours. After the end of the reaction, diethyl
ether (20 parts) was added to the reaction mixture. After the mixture had been separated
into two phases, magnesium sulfate (0.2 part) was placed in an ether phase and magnesium
sulfate was then removed by filtration, thereby obtaining a hydroxyl compound. The
hydroxyl compound was subjected to column chromatography to separate and remove components
other than principal components. Subsequently, 100 parts of the previously obtained
hydroxyl compound, 50 parts of acrylic acid, 5 parts of hydroquinone, 5 parts of p-
toluenesulfonic acid, and 200 parts of toluene were introduced into a glass flask
equipped with an agitator, a condenser, and a thermometer. Next, the flask was heated
up to 110°C and the reaction was then continued until the raw material, the hydroxyl
compound, disappeared. After the completion of the reaction, the mixture was diluted
with 200 parts of toluene, washed with an aqueous sodium hydroxide solution twice,
and then washed with ion-exchanged water three times. Subsequently, toluene was distilled
off under reduced pressure, thereby obtaining a product. The resulting product was
identified by
1H-NMR and
19F-NMR. As a result of the quantitative analysis of the product by gas chromatography,
it was found that the compound represented by the above formula (3-1-3) was a principal
component.
(Synthesis Example (A-2): Synthesis of compound represented by the above formula (3-1-4))
[0222] A product containing the compound represented by the above formula (3-1-4) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(A-1) except that an iodinated material represented by the following formula (A-e-2)
was used instead of the iodinated material represented by the above formula (A-e-1)
described in Synthesis Example (A-1).
(Synthesis Example (A-3): Synthesis of compound represented by the above formula (3-1-6))
[0223] A product containing the compound represented by the above formula (3-1-6) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(A-1) except that an iodinated material represented by the following formula (A-e-3)
was used instead of the iodinated material represented by the above formula (A-e-1)
described in Synthesis Example (A-1).
(Synthesis Example (A-4): Synthesis of compound represented by the above formula (3-1-7))
[0224] A product containing the compound represented by the above formula (3-1-7) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(A-1) except that an iodinated material represented by the following formula (A-e-4)
was used instead of the iodinated material represented by the above formula (A-e-1)
described in Synthesis Example (A-1).
(Synthesis Example (A-5): Synthesis of compound represented by the above formula (3-2-2))
[0225] In a glass flask equipped with an agitator, a condenser, and a thermometer, 100 parts
of a hydroxyl compound represented by the following formula (A-e-5):
, 50 parts of acrylic acid, 5 parts of hydroquinone, 5 parts of p-toluenesulfonic
acid, and 200 parts of toluene were placed. Subsequently, the mixture was heated up
to 110°C and the reaction was then continued until the raw material, the hydroxyl
compound, disappeared. After the completion of the reaction, the mixture was diluted
with 200 parts of toluene, washed with an aqueous sodium hydroxide solution twice,
and then washed with ion-exchanged water three times. Subsequently, toluene was distilled
off under reduced pressure, thereby obtaining a product. The resulting product was
identified by
1H-NMR and
19F-NMR. As a result of the quantitative analysis of the product by gas chromatography,
it was found that the compound represented by the above formula (3-2-2) was a principal
component.
(Synthesis Example (A-6): Synthesis of compound represented by the above formula (3-2-1))
[0226] A product containing the compound represented by the above formula (3-2-1) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(A-5) except that a hydroxyl compound represented by the following formula (A-e-6)
was used instead of the hydroxyl compound represented by the above formula (A-e-5)
described in Synthesis Example (A-5).
(Synthesis Example (A-7))
[0227] A reaction was carried out in a manner similar to that of Synthesis Example (A-1)
except that an iodinated material represented by the following formula (A-f-1):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was used instead of the iodinated material represented by the above formula (A-e-1)
described in Synthesis Example (A-1). Consequently, a product, in which a compound
represented by the following formula (A-f):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was a principal component, was obtained.
(Production Example (A-1): Production of polymer (A-A))
[0228] In a glass flask equipped with an agitator, a reflux condenser, a dropping funnel,
a thermometer, and a gas-blowing opening, 10 parts of methyl methacrylate (hereinafter,
abbreviated as MMA) and 0.3 part of an acetone (17.5%)-toluene mixture solvent were
placed. Subsequently, a nitrogen gas was introduced into the flask and then 0.5 part
of azobisisobutyronitrile (hereinafter, abbreviated as AIBN) as a polymerization initiator
and 0.32 part of thioglycolic acid as a chain transfer agent were added to initiate
polymerization under reflux. During a time period of 4.5 hours after the initiation,
90 parts of MMA was continuously dropped. In addition, 2.08 parts of thioglycolic
acid was dissolved in 7 parts of toluene and then added every 30 minutes in nine times.
Likewise, AIBN (1.5 parts) was added every 1.5 hours in three times to carry out the
polymerization. Subsequently, the mixture was refluxed for an additional two hours,
thereby terminating the polymerization. A polymer solution of the following formula
(g) was obtained:
(in the above formula, 80 represents the average number of repetitions of the repetitive
unit). The reaction temperature was 77 to 87°C. Part of the reaction solution was
re-precipitated with n-hexane and then dried, followed by obtaining an acid value
of 0.34 mg equivalent/g as a result of the measurement of acid value. An average number
of repetitions of the repetitive unit was about 80.
[0229] Next, part of acetone was distilled off from the above reaction solution, followed
by the addition of 0.5% of triethyl amine as a catalyst and 200 ppm of hydroquinone
monomethyl ether as a polymerization-prohibiting agent. In addition, 1.2-fold molar
excess of glycidyl methacrylate was added with respect to the acid value of the polymer.
Subsequently, the reaction solution was reacted for 11 hours under reflux (about 110°C).
The reaction solution was added to 10 volumes of n-hexane and then precipitated, followed
by drying at 80°C under reduced pressure. As a result, 90 parts of a compound represented
by the following formula (d-1) was obtained:
(in the above formula, 80 represents the average number of repetitions of the repetitive
unit).
[0230] Next, the following materials were placed in a glass flask equipped with an agitator,
a reflux condenser, a dropping funnel, a thermometer, and a gas-blowing opening and
then subjected to the introduction of a nitrogen gas, followed by reacting for 5 hours
under reflux (heated to about 100°C). 70 parts of a compound represented by the above
formula (d-1). 30 parts of a product in which the compound represented by the above
formula (3-1-3) obtained by Synthesis Example (A-1) was a principal component. 270
parts of trifluorotoluene. AIBN (0.35 part). The reaction solution was introduced
into 10 volumes of methanol and precipitated, followed by drying at 80°C under reduced
pressure. Consequently, a polymer (A-A: weight average molecular weight (Mw): 22,000)
having a repetitive structural unit represented by the above formula (1-1-3) was obtained.
[0231] In the present invention, the weight average molecular weights of the polymer and
the resin were measured as described below according to the conventional method.
[0232] In other words, the polymer or the resin as a measurement target was placed in tetrahydrofuran
and then left standing for several hours. After that, the measuring-target resin and
tetrahydrofuran were mixed well while being shaken (mixed until no aggregate of the
measuring-target polymer or resin was observed), followed by further allowing to stand
for 12 hours or more.
[0233] After that, a product which had been passed through a sample-treating filter, MAISHORIDISK
H-25-5 manufactured by Tosoh Corporation, was provided as a sample for gel permeation
chromatography (GPC).
[0234] Subsequently, the column was stabilized in a heat chamber at 40°C and a solvent,
tetrahydrofuran, was then fed at a flow rate of 1 ml/min to the column at the temperature.
Subsequently, 10 µl of the GPC sample was injected into the column, thereby determining
the weight average molecular weight of the measuring-target polymer or resin. The
column used was a column TSKgel SuperHM-M manufactured by Tosoh Corporation.
[0235] For determining the weight average molecular weight of the measuring-target polymer
or resin, a molecular weight distribution possessed by the measuring-target polymer
or resin was calculated from a relationship between the logarithmic values of the
standard curve prepared by several monodispersed polystryrene standard samples and
the counted values. The standard polystyrene samples used for preparing the standard
curve were monodispersed polystyrene manufactured by Sigma-Aldrich Corporation of
ten different molecular weights: 3,500; 12,000; 40,000; 75,000; 98,000; 120,000; 240,000;
500,000; 800,000; and 1,800,000. The detector used was an RI (an index of refraction)
detector.
(Production Example (A-2): Production of polymer (A-B))
[0236] The reaction and the process were carried out by the same procedures as those of
Production Example (A-1) except that the compound represented by the above formula
(3-1-3) was replaced with a product in which the compound represented by the above
formula (3-1-4) obtained in Synthesis Example (A-2) was a principal component. Consequently,
a polymer (A-B: weight average molecular weight (Mw): 21,000) having the repetitive
structural unit represented by the above formula (1-1-4) was obtained.
(Production Example (A-3): Production of polymer (A-C))
[0237] The reaction and the process were carried out by the same procedures as those of
Production Example (A-1) except that the compound represented by the above formula
(3-1-3) was replaced with a product in which the compound represented by the above
formula (3-1-6) obtained in Synthesis Example (A-3) was a principal component. Consequently,
a polymer (A-C: weight average molecular weight (Mw): 19,500) having the repetitive
structural unit represented by the above formula (1-1-6) was obtained.
(Production Example (A-4): Production of polymer (A-D))
[0238] The reaction and the process were carried out by the same procedures as those of
Production Example (A-1) except that the compound represented by the above formula
(3-1-3) was replaced with a produce in which the compound represented by the above
formula (3-1-7) obtained in Synthesis Example (A-4) was a principal component. Consequently,
a polymer (A-D: weight average molecular weight (Mw): 23,400) having the repetitive
structural unit represented by the above formula (1-1-7) was obtained.
(Production Example (A-5): Production of polymer (A-E))
[0239] The reaction and the process were carried out by the same procedures as those of
Production Example (A-1) except that the compound represented by the above formula
(3-1-3) was replaced with a product in which the compound represented by the above
formula (3-2-2) obtained in Synthesis Example (A-5) was a principal component. Consequently,
a polymer (A-E: weight average molecular weight (Mw): 22,100) having the repetitive
structural unit represented by the above formula (1-2-2) was obtained.
(Production Example (A-6): Production of polymer (A-F))
[0240] The reaction and the process were carried out by the same procedures as those of
Production Example (A-1) except that the compound represented by the above formula
(3-1-3) was replaced with a product in which the compound represented by the above
formula (3-2-1) obtained in Synthesis Example (A-6) was a principal component. Consequently,
a polymer (A-F: weight average molecular weight (Mw): 22,500) having the repetitive
structural unit represented by the above formula (1-2-1) was obtained.
(Production Example (A-7): Production of polymer (A-G)) (comparative example)
[0241] The reaction and the process were carried out by the same procedures as those of
Production Example (A-1) except that the compound represented by the above formula
(3-1-3) was replaced with a product in which the compound represented by the above
formula (A-f) obtained in Synthesis Example (A-7) was a principal component. Consequently,
a polymer (A-G: weight average molecular weight (Mw): 21,000) having the repetitive
structural unit represented by the following formula (A-f-2) was obtained:
(in the above formula, 7 represents the number of repetitions of the repetitive unit).
(Example (A-1))
[0242] A conductive support used was an aluminum cylinder (JIS-A3003, aluminum alloy ED
tube, manufactured by Showa Aluminum Corporation) with 260.5 mm in length and 30 mm
in diameter obtained by heat extrusion under the environment with a temperature of
23°C and a humidity of 60%RH.
[0243] The following materials were dispersed with a sand mill with 1-mm-diameter glass
beads for 3 hours, thereby preparing a dispersion solution. TiO
2 particles covered with oxygen-deficient SnO
2 as conductive particles (power resistivity: 80 Ω·cm, SnO
2 coverage rate (mass ratio): 50%), 6.6 parts. A phenol resin (trade name: Plyophen
J-325, manufactured by Dainippon Ink & Chemicals, Incorporated. 60% resin solid) as
a resin binder, 5.5 parts. Methoxy propanol as a solvent, 5.9 parts.
[0244] The following materials were added to the dispersion solution, and the whole was
stirred, thereby preparing a conductive-layer coating solution. Silicone resin particles
(trade name: Tospal 120, GE Toshiba Silicones, average particle size: 2 µm) as a surface-roughness
imparting agent, 0.5 part. Silicone oil (trade name: SH28PA, manufactured by Dow Corning
Toray Silicone Co., Ltd.) as a leveling agent, 0.001 part.
[0245] The support was dip-coated with the conductive-layer coating solution and the whole
was dried at a temperature of 140°C for 30 minutes to heat-curing, thereby forming
a conductive layer of 15 µm in average film thickness at a position of 130 mm from
the upper side of the support.
[0246] The conductive layer was dip-coated with the following intermediate-layer coating
solution and then the whole was dried at a temperature of 100°C for 10 minutes, thereby
forming an intermediate layer of 0.5 µm in average film thickness at a position of
130 mm from the upper end of the support. An intermediate-layer coating solution prepared
by dissolving N-methoxy methylated nylon (trade name: Toresin EF-30T, manufactured
by Teikoku Chemical Industry Co., Ltd.), 4 parts, and a copolymer nylon resin (Amilan
CM8000, manufactured by Toray Co., Ltd.), 2 parts, in a mixture solvent of 65 parts
of methanol and 30 parts of n-butanol.
[0247] Subsequently, the following materials were dispersed with a sand-milling device with
glass beads of 1 mm in diameter for 1 hour. Next, 250 parts of ethyl acetate was added
to the mixture, thereby preparing a charge-generating layer coating solution. Hydroxy
gallium phthalocyanine in crystal form with strong peaks at Bragg angles (2θ ± 0.2°)
in CuKα-characteristic X-ray diffraction of 7.5°, 9.9°, 16.3°, 18.6°, 25.1°, and 28.3°,
10 parts. Polyvinyl butyral (trade name: S-LEX BX-1, manufactured by Sekisui Chemical,
Co., Ltd.), 5 parts. Cyclohexanone, 250 parts.
[0248] The intermediate layer was dip-coated with the charge-generating layer coating solution
and then the whole was dried at a temperature of 100°C for 10 minutes, thereby forming
a charge-generating layer of 0.16 µm in average film thickness at a position of 130
mm from the upper end of the support.
[0249] Next, the following materials were dissolved in a mixture solvent of 30 parts of
dimethoxy methane and 70 parts of chlorobenzene, thereby preparing a coating solution
containing a charge-transporting substance. A charge-transporting substance having
a structure represented by the following formula (CTM-1), 10 parts:
A polycarbonate resin (Iupilon Z-400, manufactured by Mitsubishi Engineering-Plastics
Corporation) [viscosity average molecular weight (Mv): 39,000] formed of a repetitive
structural unit represented by the following formula (P-1) as a binder resin, 10 parts:
The polymer (A-A) produced in Production Example (A-1), 0.2 part.
[0250] The charge-generating layer was dip-coated with the charge-transporting layer coating
solution thus prepared and then the whole was dried at a temperature of 120°C for
30 minutes. Consequently, a charge-transporting layer with an average film thickness
of 17 µm at a position of 130 mm from the upper end of the support was formed.
[0251] Further, a method of measuring a viscosity average molecular weight (Mv) is as described
below.
[0252] First, 0.5 g of a sample was dissolved in 100 ml of methylene chloride and a specific
viscosity of the solution at a temperature of 25°C was then determined using an improved
Ubbelohde-type viscometer. Subsequently, the limiting viscosity was calculated from
the specific viscosity and the viscosity average molecular weight (Mv) was then calculated
by the Mark-Houwink viscosity formula. The viscosity average molecular weight (Mv)
was represented by the corresponding value of polystyrene determined by gel permeation
chromatography (GPC).
[0253] In this way, an electrophotographic photosensitive member having a charge-transporting
layer provided as a surface layer was prepared.
[0254] The electrophotographic photosensitive member thus prepared was evaluated for initial
blade-curling
*1 and electrophotographic properties
*2. The results are shown in Table 1.
*1: Evaluation method for initial blade-curling
[0255] The electrophotographic photosensitive member thus prepared, the main body of a laser
beam printer LBP-2510 manufactured by Canon Co. Ltd., and a process cartridge of the
main body were placed under the environment with a temperature of 35°C and a humidity
of 80%RH for 15 hours. After that, under the environment, the electrophotographic
photosensitive member thus prepared was mounted on the process cartridge, followed
by continuous output of 20 sheets of a solid white image. During the printing, whether
a curling trouble of a cleaning blade occurred was observed (the evaluation was performed
on four stations (four new electrophotographic photosensitive members and four new
process cartridges were prepared for the respective colors), and "F" was written in
Table 1 when the curling trouble occurred even only once or "A" was written when no
trouble occurred).
*2: Evaluation method for electrophotographic properties
[0256] The prepared electrophotographic photosensitive member, the main body of the laser
beam printer LBP-2510 manufactured by Canon Co., Ltd., and tools for measuring a surface
potential were placed under the environment with a temperature of 25°C and a humidity
of 50%RH (normal temperature and normal humidity) for 15 hours. Further, the tools
for measuring the surface potential were those (the toner, the developing rollers,
and the cleaning blade were removed) used for placing a probe for surface-potential
measurement of an electrophotographic photosensitive member on the developing roller
position of the process cartridge of the LBP-2510. After that, under the same environment,
the tools for measuring the surface potential of the electrophotographic photosensitive
member were attached to the member, and the surface potential of the electrophotographic
photosensitive member was then measured without sheet-feeding under the condition
in which a belt unit for electrostatic image transfer was removed. By the way, the
tools for measuring the surface potential were mounted on the station of a cyan process
cartridge in the main body and the measurement was then carried out.
[0257] A potential measurement method was carried out as described below. First, an exposure
part potential (VI: a potential at first round after exposure of the electrophotographic
photosensitive member in the presence of whole surface exposure after electrification)
was measured. Next, a pre-exposure after-potential (Vr: a potential at first cycle
(second round after electrification) after the pre-exposure without image exposure
in the presence of electrification at only first round of the electrophotographic
photosensitive member) was then measured. Subsequently, a cycle of electrification/whole-surface
image exposure/pre-exposure was repeated 1,000 times (1K cycles). After that, the
pre-exposure after-potential (in the table, represented by Vr (1K)) was measured again.
[0258] Those results were shown in Table 1.
(Examples (A-2) to (A-6))
[0259] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-1) except that the polymer (A-A) used in the charge-transporting
layer coating solution in Example (A-1) was replaced with a polymer represented in
Table 1. The results are shown in Table 1.
(Example (A-7))
[0260] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-2) except for the following change in Example (A-2).
The results are shown in Table 1
[0261] The polycarbonate resin formed of a repetitive structural unit represented by the
above formula (P-1), the binder resin of the charge-transporting layer, was replaced
with a polyarylate resin having a repetitive structural unit represented by the following
formula (P-2)(weight average molecular weight (Mw): 120,000):
[0262] By the way, a molar ratio between a terephthalic acid structure and an isophthalic
acid structure in the above polyarylate resin (tetraphthalic acid structure: isophthalic
acid structure) was 50:50.
(Example (A-8))
[0263] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-8) except that hydroxy gallium phthalocyanine as the
charge-generating substance of the charge-generating layer in Example (A-7) was replaced
with oxytitamium phthalocyanine (TiOPc) below. The results are shown in Table 1. TiOPc
with strong peaks at Bragg angles 20 ± 0.2° in CuKa-characteristic X-ray diffraction
of 9.0°, 14.2°, 23.9°, and 27.1°.
(Examples (A-9) and (A-10))
[0264] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-7) except that the polymer (A-B) used in the charge-transporting
layer coating solution in Example (A-7) was replaced with a polymer represented in
Table 1. The results are shown in Table 1.
(Example (A-11))
[0265] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-10) except that the charge-transporting substance represented
by the above formula (CTM-1) used in the charge-transporting layer coating solution
in Example (A-9) was replaced with a charge-transporting substance represented by
the following formula (CTM-2):
and a charge-transporting substance represented by the following formula (CTM-3):
where 5 parts of each charge-transporting substance was used. The results are shown
in Table 1.
(Comparative Example (A-1))
[0266] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-2) except that the polymer (A-B) was not contained in
the charge-transporting layer coating solution in Example (A-2). The results are shown
in Table 1.
(Comparative Example (A-2))
[0267] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-2) except that the polymer (A-B) used in the charge-transporting
layer coating solution in Example (A-2) was replaced with 2,6-di-tert-butyl-p-cresol
(BHT). The results are shown in Table 1.
(Comparative Example (A-3))
[0268] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-2) except that the polymer (A-B) used in the charge-transporting
layer coating solution in Example (A-2) was replaced with the polymer (A-G) produced
in Production Example (A-7). The results are shown in Table 1.
(Comparative Example (A-4))
[0269] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (A-2) except that the polymer (A-B) used in the charge-transporting
layer coating solution in Example (A-2) was replaced with a compound (trade name:
Alon GF300, manufactured by Toagosei Co., Ltd.). The results are shown in Table 1.
Table 1
|
|
Initial blade-curling |
Initial electrophotographic properties |
After endurance |
Vl (-V) |
Vr (-V) |
Vr (1K) (-V) |
Example A-1 |
Polymer A-A |
A |
125 |
35 |
45 |
Example A-2 |
Polymer A-B |
A |
125 |
35 |
45 |
Example A-3 |
Polymer A-C |
A |
120 |
35 |
45 |
Example A-4 |
Polymer A-D |
A |
120 |
30 |
40 |
Example A-5 |
Polymer A-E |
A |
120 |
25 |
30 |
Example A-6 |
Polymer A-F |
A |
120 |
25 |
30 |
Example A-7 |
Polymer A-B |
A |
120 |
35 |
45 |
Example A-8 |
Polymer A-B |
A |
125 |
40 |
50 |
Example A-9 |
Polymer A-E |
A |
120 |
25 |
30 |
Example A-10 |
Polymer A-F |
A |
120 |
25 |
30 |
Example A-11 |
Polymer A-E |
A |
120 |
25 |
30 |
|
|
|
|
|
|
Comparative Example A-1 |
- |
F |
120 |
25 |
30 |
Comparative Example A-2 |
BHT |
F |
135 |
45 |
75 |
Comparative Example A-3 |
Polymer A-G |
A |
120 |
40 |
60 |
Comparative Example A-4 |
Alon GF300 |
A |
125 |
35 |
55 |
[0270] As is evident from the above results, Examples A-1 to A-11 and Comparative Examples
A-1 and A-2 of the present invention are compared with each other, whereby the following
fact is found. Blade-curling at an initial stage can be prevented by producing an
electrophotographic photosensitive member using a compound having a repetitive unit
of the present invention as a structural component of a coating solution for the formation
of a surface layer. As a result, an electrophotographic photosensitive member avoiding
such a trouble can be provided.
[0271] In addition, by comparing Examples A-1 to A-11 and Comparative Example A-3 of the
present invention with each other, the branched structure in the compound having the
repetitive unit of the present invention is shown to be excellent in repetitive property
out of the electrophotographic properties.
[0272] Further, Examples A-1 to A-11 and Comparative Example A-4 of the present invention
are compared with each other, whereby the following a fact is found. An electrophotographic
photosensitive member is produced by using a compound having a repetitive unit of
the present invention as a structural component of a coating solution for the formation
of a surface layer. As a result, the member is more excellent in the repetitive property
out of the electrophotographic properties than that in the case where the compound
of Comparative Example 4 is used.
(Synthesis Example (B-1): Synthesis of compound represented by the above formula (3-2-2))
[0273] An iodinated material (0.5 part) represented by the following formula (B-e-1):
and ion-exchanged water (20 parts) were charged into a deaerated autoclave, followed
by heating up to 300°C to carry out a conversion reaction of iodine to a hydroxyl
group at a gauge pressure of 9.2 MPa for 4 hours. After the end of the reaction, diethyl
ether (20 parts) was added to the reaction mixture. After the mixture had been separated
into two phases, magnesium sulfate (0.2 part) was placed in an ether phase and magnesium
sulfate was then removed by filtration, thereby obtaining a hydroxyl compound. The
hydroxyl compound was subjected to column chromatography to separate and remove components
other than principal components. Subsequently, 100 parts of the previously obtained
hydroxyl compound, 50 parts of acrylic acid, 5 parts of hydroquinone, 5 parts of p-
toluenesulfonic acid, and 200 parts of toluene were introduced into a glass flask
equipped with an agitator, a condenser, and a thermometer. Next, the flask was heated
up to 110°C and the reaction was then continued until the raw material, the hydroxyl
compound, disappeared. After the completion of the reaction, the mixture was diluted
with 200 parts of toluene, washed with an aqueous sodium hydroxide solution twice,
and then washed with ion-exchanged water three times. Subsequently, toluene was distilled
off under reduced pressure, thereby obtaining a product. The resulting product was
identified by
1H-NMR and
19F-NMR. As a result of the quantitative analysis of the product by gas chromatography,
it was found that the compound represented by the above formula (3-3-2) was a principal
component.
(Synthesis Example (B-2): Synthesis of compound represented by the above formula (3-3-6))
[0274] A product containing the compound represented by the above formula (3-3-6) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(B-1) except that an iodinated material represented by the following formula (B-e-2)
was used instead of the iodinated material represented by the above formula (B-e-1)
described in Synthesis Example (B-1).
(Synthesis Example (B-3))
[0275] A reaction was carried out in a manner similar to that of Synthesis Example (B-1)
except that an iodinated material represented by the following formula (B-f-1):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was used instead of the iodinated material represented by the above formula (B-e-1)
described in Synthesis Example (B-1). Consequently, a product, in which a compound
represented by the following formula (B-f):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was a principal component, was obtained.
(Production Example (B-1): Production of polymer (B-A))
[0276] In a glass flask equipped with an agitator, a reflux condenser, a dropping funnel,
a thermometer, and a gas-blowing opening, 10 parts of methyl methacrylate (hereinafter,
abbreviated as MMA) and 0.3 part of an acetone (17.5%)-toluene mixture solvent were
placed. Subsequently, a nitrogen gas was introduced into the flask and then 0.5 part
of azobisisobutyronitrile (hereinafter, abbreviated as AIBN) as a polymerization initiator
and 0.32 part of thioglycolic acid as a chain transfer agent were added to initiate
polymerization under reflux. During a time period of 4.5 hours after the initiation,
90 parts of MMA was continuously dropped. In addition, 2.08 parts of thioglycolic
acid was dissolved in 7 parts of toluene and then added every 30 minutes in nine times.
Likewise, AIBN (1.5 parts) was added every 1.5 hours in three times to carry out the
polymerization. Subsequently, the mixture was refluxed for an additional two hours,
thereby terminating the polymerization. A polymer solution of the above formula (g)
was obtained. The reaction temperature was 77 to 87°C. Part of the reaction solution
was re-precipitated with n-hexane and then dried, followed by obtaining an acid value
of 0.34 mg equivalent/g as a result of the measurement of acid value. An average number
of repetitions of the repetitive unit was about 80.
[0277] Next, part of acetone was distilled off from the above reaction solution, followed
by the addition of 0.5% of triethyl amine as a catalyst and 200 ppm of hydroquinone
monomethyl ether as a polymerization-prohibiting agent. In addition, 1.2-fold molar
excess of glycidyl methacrylate was added with respect to the acid value of the polymer.
Subsequently, the reaction solution was reacted for 11 hours under reflux (about 110°C).
The reaction solution was added to 10 volumes of n-hexane and then precipitated, followed
by drying at 80°C under reduced pressure. As a result, 90 parts of a compound represented
by the above formula (d-1) was obtained.
[0278] Next, the following materials were placed in a glass flask equipped with an agitator,
a reflux condenser, a dropping funnel, a thermometer, and a gas-blowing opening and
then subjected to the introduction of a nitrogen gas, followed by reacting for 5 hours
under reflux (heated to about 100°C). 70 parts of a compound represented by the above
formula (d-1). 30 parts of a product in which a compound represented by the above
formula (3-2-2) obtained in Synthesis Example (B-1) was a principal component. 270
parts of trifluorotoluene. AIBN (0.35 part). The reaction solution was introduced
into 10 volumes of methanol and precipitated, followed by drying at 80°C under reduced
pressure. Consequently, a polymer (B-A: weight average molecular weight (Mw): 24,000)
having a repetitive structural unit represented by the above formula (1-3-2) was obtained.
(Production Example (B-2): Production of polymer (B-B))
[0279] The reaction and the process were carried out by the same procedures as those of
Production Example (B-1) except that the compound represented by the above formula
(3-3-2) was replaced with a product in which the compound represented by the above
formula (3-3-6) obtained in Synthesis Example (B-2) was a principal component. Consequently,
a polymer (B-B: weight average molecular weight 23,000) having the repetitive structural
unit represented by the above formula (1-3-6) was obtained.
(Production Example (B-3): Production of polymer (B-C)) (comparative example)
[0280] The reaction and the process were carried out by the same procedures as those of
Production Example (B-1) except that the compound represented by the above formula
(3-3-2) was replaced with a product in which the compound represented by the above
formula (B-f) obtained in Synthesis Example (B-3) was a principal component. Consequently,
a polymer (B-C: weight average molecular weight 21,000) having the repetitive structural
unit represented by the following formula (B-f-2) was obtained:
(in the above formula, 7 represents the number of repetitions of the repetitive unit).
(Example (B-1))
[0281] A conductive support used was an aluminum cylinder (JIS-A3003, aluminum alloy ED
tube, manufactured by Showa Aluminum Corporation) with 260.5 mm in length and 30 mm
in diameter obtained by heat extrusion under the environment with a temperature of
23°C and a humidity of 60%RH.
[0282] The following materials were dispersed with a sand mill with 1-mm-diameter glass
beads for 3 hours, thereby preparing a dispersion solution. TiO
2 particles covered with oxygen-deficient SnO
2 as conductive particles (power resistivity: 80 Ω·cm, SnO
2 coverage rate (mass ratio): 50%), 6.6 parts. A phenol resin (trade name: Plyophen
J-325, manufactured by Dainippon Ink & Chemicals, Incorporated. 60% resin solid) as
a resin binder, 5.5 parts. Methoxy propanol as a solvent, 5.9 parts.
[0283] The following materials were added to the dispersion solution, and the whole was
stirred, thereby preparing a conductive-layer coating solution. Silicone resin particles
(trade name: Tospal 120, GE Toshiba Silicones, average particle size: 2 µm) as a surface-roughness
imparting agent, 0.5 part. Silicone oil (trade name: SH28PA, manufactured by Dow Corning
Toray Silicone Co., Ltd.) as a leveling agent, 0.001 part.
[0284] The support was dip-coated with the conductive-layer coating solution and the whole
was dried at a temperature of 140°C for 30 minutes to heat-curing, thereby forming
a conductive layer of 15 µm in average film thickness at a position of 130 mm from
the upper side of the support.
[0285] The conductive layer was dip-coated with the following intermediate-layer coating
solution and then the whole was dried at a temperature of 100°C for 10 minutes, thereby
forming an intermediate layer of 0.5 µm in average film thickness at a position of
130 mm from the upper end of the support. An intermediate-layer coating solution prepared
by dissolving N-methoxy methylated nylon (trade name: Toresin EF-30T, manufactured
by Teikoku Chemical Industry Co., Ltd.), 4 parts, and a copolymer nylon resin (Amilan
CM8000, manufactured by Toray Co., Ltd.), 2 parts, in a mixture solvent of 65 parts
of methanol and 30 parts of n-butanol.
[0286] Subsequently, the following materials were dispersed with a sand-milling device with
glass beads of 1 mm in diameter for 1 hour. Next, 250 parts of ethyl acetate was added
to the mixture, thereby preparing a charge-generating layer coating solution. Hydroxy
gallium phthalocyanine in crystal form with strong peaks at Bragg angles (2θ ± 0.2°)
in CuKα-characteristic X-ray diffraction of 7.5°, 9.9°, 16.3°, 18.6°, 25.1°, and 28.3°,
10 parts. Polyvinyl butyral (trade name: S-LEX BX-1, manufactured by Sekisui Chemical,
Co., Ltd.), 5 parts. Cyclohexanone, 250 parts.
[0287] The intermediate layer was dip-coated with the charge-generating layer coating solution
and then the whole was dried at a temperature of 100°C for 10 minutes, thereby forming
a charge-generating layer of 0.16 µm in average film thickness at a position of 130
mm from the upper end of the support.
[0288] Next, the following materials were dissolved in a mixture solvent of 30 parts of
dimethoxy methane and 70 parts of chlorobenzene, thereby preparing a coating solution
containing a charge-transporting substance. A charge-transporting substance having
a structure represented by the above formula (CTM-1), 10 parts. A polycarbonate resin
(Iupilon Z-400, manufactured by Mitsubishi Engineering-Plastics Corporation) [viscosity
average molecular weight (Mv): 39,000] formed of a repetitive structural unit represented
by the above formula (P-1) as a binder resin, 10 parts. A polymer produced in Production
Example (B-1) (B-A: 0.2 part).
[0289] The charge-generating layer was dip-coated with the charge-transporting layer coating
solution thus prepared and then the whole was dried at a temperature of 120°C for
30 minutes. Consequently, a charge-transporting layer with an average film thickness
of 17 µm at a position of 130 mm from the upper end of the support was formed.
[0290] In this way, an electrophotographic photosensitive member having a charge-transporting
layer provided as a surface layer was prepared.
[0291] The electrophotographic photosensitive member thus prepared was evaluated for initial
blade-curling
*1 and electrophotographic properties
*2. The results are shown in Table 1.
*1: Evaluation method for initial blade-curling
[0292] The electrophotographic photosensitive member thus prepared, the main body of a laser
beam printer LBP-2510 manufactured by Canon Co. Ltd., and a process cartridge of the
main body were placed under the environment with a temperature of 35°C and a humidity
of 80%RH for 15 hours. After that, under the environment, the electrophotographic
photosensitive member thus prepared was mounted on the process cartridge, followed
by continuous output of 20 sheets of a solid white image. During the printing, whether
a curling trouble of a cleaning blade occurred was observed (the evaluation was performed
on four stations (four new electrophotographic photosensitive members and four new
process cartridges were prepared for the respective colors), and "F" was written in
Table 1 when the curling trouble occurred even only once or "A" was written when no
trouble occurred).
*2: Evaluation method for electrophotographic properties
[0293] The prepared electrophotographic photosensitive member, the main body of the laser
beam printer LBP-2510 manufactured by Canon Co., Ltd., and tools for measuring a surface
potential were placed under the environment with a temperature of 25°C and a humidity
of 50%RH (normal temperature and normal humidity) for 15 hours. Further, the tools
for measuring the surface potential were those (the toner, the developing rollers,
and the cleaning blade were removed) used for placing a probe for surface-potential
measurement of an electrophotographic photosensitive member on the developing roller
position of the process cartridge of the LBP-2510. After that, under the same environment,
the tools for measuring the surface potential of the electrophotographic photosensitive
member were attached to the member, and the surface potential of the electrophotographic
photosensitive member was then measured without sheet-feeding under the condition
in which a belt unit for electrostatic image transfer was removed. By the way, the
tools for measuring the surface potential were mounted on the station of a cyan process
cartridge in the main body and the measurement was then carried out.
[0294] A potential measurement method was carried out as described below. First, an exposure
part potential (VI: a potential at first round after exposure of the electrophotographic
photosensitive member with whole surface exposure after electrification) was measured.
Next, a pre-exposure after-potential (Vr: a potential at first cycle (second round
after electrification) after the pre-exposure without image exposure with electrification
at only first round of the electrophotographic photosensitive member) was then measured.
Subsequently, a cycle of electrification/whole-surface image exposure/pre-exposure
was repeated 1,000 times (1K cycles). After that, the pre-exposure after-potential
(in the table, represented by Vr (1K)) was measured again.
[0295] Those results were shown in Table 2.
(Example (B-2))
[0296] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-1) except that the polymer (B-A) used in the charge-transporting
layer coating solution in Example (B-1) was replaced with the polymer (B-B) produced
in Production Example (B-2). The results are shown in Table 2.
(Example (B-3))
[0297] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-1) except for the following change in Example (B-1).
The results are shown in Table 2.
[0298] The polycarbonate resin formed of a repetitive structural unit represented by the
above formula (P-1), the binder resin of the charge-transporting layer, was replaced
with a polyarylate resin having a repetitive structural unit represented by the above
formula (P-2)(weight average molecular weight (Mw): 120,000).
[0299] By the way, a molar ratio between a terephthalic acid structure and an isophthalic
acid structure in the above polyarylate resin (tetraphthalic acid structure: isophthalic
acid structure) was 50:50.
(Example (B-4))
[0300] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-4) except that hydroxy gallium phthalocyanine as the
charge-generating substance of the charge-generating layer in Example (B-3) was replaced
with oxytitanium phthalocyanine (TiOPc) below. The results are shown in Table 2. TiOPc
with strong peaks at Bragg angles 2θ ± 0.2° in CuKα-characteristic X-ray diffraction
of 9.0°, 14.2°, 23.9°, and 27.1°.
(Example (B-5))
[0301] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-5) except that the charge-transporting substance represented
by the above formula (CTM-1) used in the charge-transporting layer coating solution
in Example (B-4) was replaced with a charge-transporting substance represented by
the above formula (CTM-2) and a charge-transporting substance represented by the above
formula (CTM-3). 5 parts of each charge-transporting substance was used. The results
are shown in Table 2.
(Comparative Example (B-1))
[0302] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-1) except that the polymer (B-A) was not included in
the charge-transporting layer coating solution in Example (B-1). The results are shown
in Table 2.
(Comparative Example (B-2))
[0303] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-1) except that the polymer (B-A) used in the charge-transporting
layer coating solution in Example (B-1) was replaced with 2,6-di-tert-butyl-p-cresol
(BHT). The results are shown in Table 2.
(Comparative Example (B-3))
[0304] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-1) except that the polymer (B-A) used in the charge-transporting
layer coating solution in Example (B-1) was replaced with the polymer (B-E) produced
in Production Example (B-3). The results are shown in Table 2.
(Comparative Example (B-4))
[0305] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (B-1) except that the polymer (B-A) used in the charge-transporting
layer coating solution in Example (B-1) was replaced with a compound (trade name:
Alon GF300, manufactured by Toagosei Co., Ltd.). The results are shown in Table 2.
Table 2
|
|
Initial blade-curling |
Initial electrophotographic properties |
After endurance |
Vl (-V) |
Vr (-V) |
Vr (1K) (-V) |
Example B-1 |
Polymer B-A |
A |
125 |
30 |
40 |
Example B-2 |
Polymer B-B |
A |
120 |
30 |
40 |
Example B-3 |
Polymer B-A |
A |
120 |
35 |
40 |
Example B-4 |
Polymer B-A |
A |
120 |
25 |
30 |
Example B-5 |
Polymer B-A |
A |
125 |
30 |
35 |
|
|
|
|
|
|
Comparative Example B-1 |
- |
F |
120 |
25 |
30 |
Comparative Example B-2 |
BHT |
F |
135 |
45 |
75 |
Comparative Example B-3 |
Polymer B-E |
A |
120 |
40 |
360 |
Comparative Example B-4 |
Alon GF300 |
A |
125 |
35 |
55 |
[0306] As is evident from the above results, Examples (B-1) to (B-5) of the present invention
and Comparative Examples (B-1) and (B-2) are compared with each other, whereby the
following fact is found. Blade-curling at an initial stage can be prevented by producing
an electrophotographic photosensitive member using a compound having a repetitive
unit of the present invention as a constitutional component of a coating solution
for the formation of a surface layer. As a result, an electrophotographic photosensitive
member avoiding such a trouble can be provided.
[0307] In addition, by comparing Examples (B-1) to (B-5) of the present invention and Comparative
Example (B-3) with each other, the compound having the repetitive unit of the present
invention is shown to be excellent in repetitive property out of the electrophotographic
properties.
[0308] Further, Examples (B-1) to (B-5) of the present invention and Comparative Example
(B-4) are compared with each other, whereby the following fact is found. An electrophotographic
photosensitive member is produced by using a compound having a repetitive unit of
the present invention as a constitutional component of a coating solution for the
formation of a surface layer. As a result, the member is more excellent in the repetitive
property out of the electrophotographic properties than that in the case where the
compound of Comparative Example 4 is used.
(Synthesis Example (C-1): Synthesis of compound represented by the above formula (3-4-1))
[0309] An iodinated material (0.5 part) represented by the following formula (C-e-1):
and ion-exchanged water (20 parts) were charged into a deaerated autoclave, followed
by heating up to 300°C to carry out a conversion reaction of iodine to a hydroxyl
group at a gauge pressure of 9.2 MPa for 4 hours. After the end of the reaction, diethyl
ether (20 parts) was added to the reaction mixture. After the mixture had been separated
into two phases, magnesium sulfate (0.2 part) was placed in an ether phase and magnesium
sulfate was then removed by filtration, thereby obtaining a hydroxyl compound. The
hydroxyl compound was subjected to column chromatography to separate and remove components
other than principal components. Subsequently, 100 parts of the previously obtained
hydroxyl compound, 50 parts of acrylic acid, 5 parts of hydroquinone, 5 parts of p-
toluenesulfonic acid, and 200 parts of toluene were introduced into a glass flask
equipped with an agitator, a condenser, and a thermometer. Next, the flask was heated
up to 110°C and the reaction was then continued until the raw material, the hydroxyl
compound, disappeared. After the completion of the reaction, the mixture was diluted
with 200 parts of toluene, washed with an aqueous sodium hydroxide solution twice,
and then washed with ion-exchanged water three times. Subsequently, toluene was distilled
off under reduced pressure, thereby obtaining a product. The resulting product was
identified by
1H-NMR and
19F-NMR. As a result of the quantitative analysis of the product by gas chromatography,
it was found that the compound represented by the above formula (3-4-1) was a principal
component.
(Synthesis Example (C-2): Synthesis of compound represented by the above formula (3-4-3))
[0310] A product containing the compound represented by the above formula (3-4-3) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(C-1) except that an iodinate material represented by the following formula (C-e-2)
was used instead of the iodinated material represented by the above formula (C-e-1)
described in Synthesis Example (C-1).
(Synthesis Example (C-3): Synthesis of compound represented by the above formula (3-4-6))
[0311] A product containing the compound represented by the above formula (3-4-6) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(C-1) except that an iodinated material represented by the following formula (C-e-3)
was used instead of the iodinated material represented by the above formula (C-e-1)
described in Synthesis Example (C-1).
(Synthesis Example (C-4))
[0312] A reaction was carried out in a manner similar to that of Synthesis Example (C-1)
except that an iodinated material represented by the following formula (C-f-1):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was used instead of the iodinated material represented by the above formula (C-e-1)
described in Synthesis Example (C-1). Consequently, a product, in which a compound
represented by the following formula (C-f):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was a principal component, was obtained.
(Production Example (C-1): Production of polymer (C-A))
[0313] In a glass flask equipped with an agitator, a reflux condenser, a dropping funnel,
a thermometer, and a gas-blowing opening, 10 parts of methyl methacrylate (hereinafter,
abbreviated as MMA) and 0.3 part of an acetone (17.5%)-toluene mixture solvent were
placed. Subsequently, a nitrogen gas was introduced into the flask and then 0.5 part
of azobisisobutyronitrile (hereinafter, abbreviated as AIBN) as a polymerization initiator
and 0.32 part of thioglycolic acid as a chain transfer agent were added to initiate
polymerization under reflux. During a time period of 4.5 hours after the initiation,
90 parts of MMA was continuously dropped. In addition, 2.08 parts of thioglycolic
acid was dissolved in 7 parts of toluene and then added every 30 minutes in nine times.
Likewise, AIBN (1.5 parts) was added every 1.5 hours in three times to carry out the
polymerization. Subsequently, the mixture was refluxed for an additional two hours,
thereby terminating the polymerization. A polymer solution of the above formula (g)
was obtained. The reaction temperature was 77 to 87°C. Part of the reaction solution
was re-precipitated with n-hexane and then dried, followed by obtaining an acid value
of 0.34 mg equivalent/g as a result of the measurement of acid value. An average number
of repetitions of the repetitive unit was about 80.
[0314] Next, part of acetone was distilled off from the above reaction solution, followed
by the addition of 0.5% of triethyl amine as a catalyst and 200 ppm of hydroquinone
monomethyl ether as a polymerization-prohibiting agent. In addition, 1.2-fold molar
excess of glycidyl methacrylate was added with respect to the acid value of the polymer.
Subsequently, the reaction solution was reacted for 11 hours under reflux (about 110°C).
The reaction solution was added to 10 volumes of n-hexane and then precipitated, followed
by drying at 80°C under reduced pressure. As a result, 90 parts of a compound represented
by the above formula (d-1) was obtained.
[0315] Next, the following materials were placed in a glass flask equipped with an agitator,
a reflux condenser, a dropping funnel, a thermometer, and a gas-blowing opening and
then subjected to the introduction of a nitrogen gas, followed by reacting for 5 hours
under reflux (heated to about 100°C). 70 parts of a compound represented by the above
formula (d-1). 30 parts of a product in which compound represented by the above formula
(3-4-1) obtained in Synthesis Example (C-1) was a principal component. 270 parts of
trifluorotoluene. AIBN (0.35 part). The reaction solution was introduced into 10 volumes
of methanol and precipitated, followed by drying at 80°C under reduced pressure. Consequently,
a polymer (C-A: weight average molecular weight (Mw): 21,000) having a repetitive
structural unit represented by the above formula (1-4-1) was obtained.
[0316] The weight average molecular weight of the polymer was determined in a manner similar
to the measurement method as described above.
(Production Example (C-2): Production of polymer (C-B))
[0317] The reaction and the process were carried out by the same procedures as those of
Production Example (C-1) except that the compound represented by the above formula
(3-4-1) was replaced with a product in which the compound represented by the above
formula (3-4-3) obtained in Synthesis Example (C-2) was a principal component. Consequently,
a polymer (C-B: weight average molecular weight (Mw) = 20,000) having the repetitive
structural unit represented by the above formula (1-4-3) was obtained.
(Production Example (C-3): Production of polymer (C-C))
[0318] The reaction and the process were carried out by the same procedures as those of
Production Example (C-1) except that the compound represented by the above formula
(3-4-1) was replaced with a product in which the compound represented by the above
formula (3-4-6) obtained in Synthesis Example (C-3) was a principal component. Consequently,
a polymer (C-C: weight average molecular weight (Mw) = 23,000) having the repetitive
structural unit represented by the above formula (1-4-6) was obtained.
(Production Example (C-4): Production of polymer (C-D)) (comparative example)
[0319] The reaction and the process were carried out by the same procedures as those of
Production Example (C-1) except that the compound represented by the above formula
(3-4-1) was replaced with a product in which the compound represented by the above
formula (C-f) obtained in Synthesis Example (C-4) was a principal component. Consequently,
a polymer (C-D: weight average molecular weight (Mw) = 21,000) having the repetitive
structural unit represented by the following formula (C-f-2) was obtained:
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
(Example (C-1))
[0320] A conductive support used was an aluminum cylinder (JIS-A3003, aluminum alloy ED
tube, manufactured by Showa Aluminum Corporation) with 260.5 mm in length and 30 mm
in diameter obtained by heat extrusion under the environment with a temperature of
23°C and a humidity of 60%RH.
[0321] The following materials were dispersed with a sand mill with 1-mm-diameter glass
beads for 3 hours, thereby preparing a dispersion solution. TiO
2 particles covered with oxygen-deficient SnO
2 as conductive particles (power resistivity: 80 Ω·cm, SnO
2 coverage rate (mass ratio): 50%), 6.6 parts. A phenol resin (trade name: Plyophen
J-325, manufactured by Dainippon Ink & Chemicals, Incorporated. 60% resin solid) as
a resin binder, 5.5 parts. Methoxy propanol as a solvent, 5.9 parts.
[0322] The following materials were added to the dispersion solution, and the whole was
stirred, thereby preparing a conductive-layer coating solution. Silicone resin particles
(trade name: Tospal 120, GE Toshiba Silicones, average particle size: 2 µm) as a surface-roughness
imparting agent, 0.5 part. Silicone oil (trade name: SH28PA, manufactured by Dow Corning
Toray Silicone Co., Ltd.) as a leveling agent, 0.001 part.
[0323] The support was dip-coated with the conductive-layer coating solution and the whole
was dried at a temperature of 140°C for 30 minutes to heat-curing, thereby forming
a conductive layer of 15 µm in average film thickness at a position of 130 mm from
the upper side of the support.
[0324] The conductive layer was dip-coated with the following intermediate-layer coating
solution and then the whole was dried at a temperature of 100°C for 10 minutes, thereby
forming an intermediate layer of 0.5 µm in average film thickness at a position of
130 mm from the upper end of the support. An intermediate-layer coating solution prepared
by dissolving N-methoxy methylated nylon (trade name: Toresin EF-30T, manufactured
by Teikoku Chemical Industry Co., Ltd.), 4 parts, and a copolymer nylon resin (Amilan
CM8000, manufactured by Toray Co., Ltd.), 2 parts, in a mixture solvent of 65 parts
of methanol and 30 parts of n-butanol.
[0325] Subsequently, the following materials were dispersed with a sand-milling device with
glass beads of 1 mm in diameter for 1 hour. Next, 250 parts of ethyl acetate was added
to the mixture, thereby preparing a charge-generating layer coating solution. Hydroxy
gallium phthalocyanine in crystal form with strong peaks at Bragg angles (2θ ± 0.2°)
in CuKα-characteristic X-ray diffraction of 7.5°, 9.9°, 16.3°, 18.6°, 25.1°, and 28.3°,
10 parts. Polyvinyl butyral (trade name: S-LEX BX-1, manufactured by Sekisui Chemical,
Co., Ltd.), 5 parts. Cyclohexanone, 250 parts.
[0326] The intermediate layer was dip-coated with the charge-generating layer coating solution
and then the whole was dried at a temperature of 100°C for 10 minutes, thereby forming
a charge-generating layer of 0.16 µm in average film thickness at a position of 130
mm from the upper end of the support.
[0327] Next, the following materials were dissolved in a mixture solvent of 30 parts of
dimethoxy methane and 70 parts of chlorobenzene, thereby preparing a coating solution
containing a charge-transporting substance. A charge-transporting substance having
a structure represented by the above formula (CTM-1), 10 parts. A polycarbonate resin
(Iupilon Z-400, manufactured by Mitsubishi Engineering-Plastics Corporation) [viscosity
average molecular weight (Mv): 39,000] formed of a repetitive structural unit represented
by the above formula (P-1) as a binder resin, 10 parts. A polymer produced in Production
Example (C-1) (C-A: 0.2 part).
[0328] The charge-generating layer was dip-coated with the charge-transporting layer coating
solution thus prepared and then the whole was dried at a temperature of 120°C for
30 minutes. Consequently, a charge-transporting layer with an average film thickness
of 17 µm at a position of 130 mm from the upper end of the support was formed.
[0329] Consequently, the electrophotographic photosensitive member in which the charge-transporting
layer was provided as a surface layer was prepared.
[0330] The electrophotographic photosensitive member thus prepared was evaluated for initial
blade-curling
*1 and electrophotographic properties
*2. The results are shown in Table 3.
*1: Evaluation method for initial blade-curling
[0331] The electrophotographic photosensitive member thus prepared, the main body of a laser
beam printer LBP-2510 manufactured by Canon Co. Ltd., and a process cartridge of the
main body were placed under the environment with a temperature of 35°C and a humidity
of 80%RH for 15 hours. After that, under the environment, the electrophotographic
photosensitive member thus prepared was mounted on the process cartridge, followed
by continuous output of 20 sheets of a solid white image. During the printing, whether
a curling trouble of a cleaning blade occurred was observed (the evaluation was performed
on four stations (four new electrophotographic photosensitive members and four new
process cartridges were prepared for the respective colors), and "F" was written in
Table 1 when the curling trouble occurred even only once or "A" was written when no
trouble occurred).
*2: Evaluation method for electrophotographic properties
[0332] The prepared electrophotographic photosensitive member, the main body of the laser
beam printer LBP-2510 manufactured by Canon Co., Ltd., and tools for measuring a surface
potential were placed under the environment with a temperature of 25°C and a humidity
of 50%RH (normal temperature and normal humidity) for 15 hours. Further, the tools
for measuring the surface potential were those (the toner, the developing rollers,
and the cleaning blade were removed) used for placing a probe for surface-potential
measurement of an electrophotographic photosensitive member on the developing roller
position of the process cartridge of the LBP-2510. After that, under the same environment,
the tools for measuring the surface potential of the electrophotographic photosensitive
member were attached to the member, and the surface potential of the electrophotographic
photosensitive member was then measured without sheet-feeding under the condition
in which a belt unit for electrostatic image transfer was removed. By the way, the
tools for measuring the surface potential were mounted on the station of a cyan process
cartridge in the main body and the measurement was then carried out.
[0333] A potential measurement method was carried out as described below. First, an exposure
part potential (VI: a potential at first round after exposure of the electrophotographic
photosensitive member with whole surface exposure after electrification) was measured.
Next, a pre-exposure after-potential (Vr: a potential at first cycle (second round
after electrification) after the pre-exposure without image exposure with electrification
at only first round of the electrophotographic photosensitive member) was then measured.
Subsequently, a cycle of electrification/whole-surface image exposure/pre-exposure
was repeated 1,000 times (1K cycles). After that, the pre-exposure after-potential
(in the table, represented by Vr (1K)) was measured again.
[0334] Those results were shown in Table 3.
(Example (C-2))
[0335] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except that the polymer (C-A) used in the charge-transporting
layer coating solution in Example (C-1) was replaced with the polymer (C-B) produced
in Production Example (C-2). The results are shown in Table 3.
(Example (C-3))
[0336] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except that the polymer (C-A) used in the charge-transporting
layer coating solution in Example (C-1) was replaced with the polymer (C-C) produced
in Production Example (C-3). The results are shown in Table 3.
(Example (C-4))
[0337] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except for the following change in Example (C-1).
The results are shown in Table 3.
[0338] The polycarbonate resin formed of a repetitive structural unit represented by the
above formula (P-1), the binder resin of the charge-transporting layer, was replaced
with a polyarylate resin having a repetitive structural unit represented by the above
formula (P-2)(weight average molecular weight (Mw): 120,000).
[0339] By the way, a molar ratio between a terephthalic acid structure and an isophthalic
acid structure in the above polyarylate resin (tetraphthalic acid structure: isophthalic
acid structure) was 50:50.
(Example (C-5))
[0340] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-4) except that hydroxy gallium phthalocyanine as the
charge-generating substance of the charge-generating layer in Example (C-4) was replaced
with oxytitanium phthalocyanine (TiOPc) below. The results are shown in Table 3. TiOPc
with strong peaks at Bragg angles 2θ ± 0.2° in CuKα-characteristic X-ray diffraction
of 9.0°, 14.2°, 23.9°, and 27.1°.
(Example (C-6))
[0341] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-5) except that the charge-transporting substance represented
by the above formula (CTM-1) used in the charge-transporting layer coating solution
in Example (C-5) was replaced with a charge-transporting substance represented by
the above formula (CTM-2) and a charge-transporting substance represented by the above
formula (CTM-3). 5 parts of each charge-transporting substance was used. The results
are shown in Table 3.
(Comparative Example (C-1))
[0342] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except that the polymer (C-A) was not included in
the charge-transporting layer coating solution in Example (C-1). The results are shown
in Table 3.
(Comparative Example (C-2))
[0343] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except that the polymer (C-A) used in the charge-transporting
layer coating solution in Example (C-1) was replaced with 2,6-di-tert-butyl-p-cresol
(BHT). The results are shown in Table 3.
(Comparative Example (C-3))
[0344] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except that the polymer (C-A) used in the charge-transporting
layer coating solution in Example (C-1) was replaced with the polymer (C-D) produced
in Production Example (C-4). The results are shown in Table 3.
(Comparative Example (C-4))
[0345] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (C-1) except that the polymer (C-A) used in the charge-transporting
layer coating solution in Example (C-1) was replaced with a compound (trade name:
Alon GF300, manufactured by Toagosei Co., Ltd.). The results are shown in Table 3.
Table 3
|
|
Initial blade- curling |
Initial electrophotographic properties |
After endurance |
Vl (-V) |
Vr(-V) |
Vr(1K)(-V) |
Example C-1 |
Polymer C-A |
A |
120 |
35 |
45 |
Example C-2 |
Polymer C-B |
A |
120 |
25 |
30 |
Example C-3 |
Polymer C-C |
A |
125 |
30 |
35 |
Example C-4 |
Polymer C-A |
A |
125 |
35 |
45 |
Example C-5 |
Polymer C-A |
A |
125 |
30 |
35 |
Example C-6 |
Polymer C-A |
A |
120 |
25 |
30 |
|
|
|
|
|
|
Comparative Example C-1 |
- |
F |
120 |
25 |
30 |
Comparative Example C-2 |
BHT |
F |
135 |
45 |
75 |
Comparative Example C-3 |
Polymer C-D |
A |
120 |
40 |
60 |
Comparative Example C-4 |
Alon GF300 |
A |
125 |
35 |
55 |
[0346] As is evident from the above results, Examples (C-1) to (C-6) of the present invention
and Comparative Examples (C-1) and (C-2) are compared with each other, whereby the
following fact is found. Blade-curling at an initial stage can be prevented by producing
an electrophotographic photosensitive member using a compound having a repetitive
unit of the present invention as a constitutional component of a coating solution
for the formation of a surface layer. As a result, an electrophotographic photosensitive
member avoiding such a trouble can be provided.
[0347] In addition, by comparing Examples (C-1) to (C-6) and Comparative Example (C-3) of
the present invention with each other, the compound having the repetitive unit of
the present invention is shown to be excellent in repetitive property out of the electrophotographic
properties.
[0348] Further, Examples (C-1) to (C-6) of the present invention and Comparative Example
(C-4) are compared with each other, whereby the following fact is found. An electrophotographic
photosensitive member is produced by using a compound having a repetitive unit of
the present invention as a constitutional component of a coating solution for the
formation of a surface layer. As a result, the member is more excellent in the repetitive
property out of the electrophotographic properties than that in the case where the
compound of Comparative Example 4 is used.
(Synthesis Example (D-1): Synthesis of compound represented by the above formula (3-5-3))
[0349] An iodinated material (0.5 part) represented by the following formula (D-e-1):
and ion-exchanged water (20 parts) were charged into a deaerated autoclave, followed
by heating up to 300°C to carry out a conversion reaction of iodine to a hydroxyl
group at a gauge pressure of 9.2 MPa for 4 hours.
[0350] After the end of the reaction, diethyl ether (20 parts) was added to the reaction
mixture. After the mixture had been separated into two phases, magnesium sulfate (0.2
part) was placed in an ether phase and magnesium sulfate was then removed by filtration,
thereby obtaining a hydroxyl compound. The hydroxyl compound was subjected to column
chromatography to separate and remove components other than principal components.
Subsequently, 100 parts of the previously obtained hydroxyl compound, 50 parts of
acrylic acid, 5 parts of hydroquinone, 5 parts of p- toluenesulfonic acid, and 200
parts of toluene were introduced into a glass flask equipped with an agitator, a condenser,
and a thermometer. Next, the flask was heated up to 110°C and the reaction was then
continued until the raw material, the hydroxyl compound, disappeared. After the completion
of the reaction, the mixture was diluted with 200 parts of toluene, washed with an
aqueous sodium hydroxide solution twice, and then washed with ion-exchanged water
three times. Subsequently, toluene was distilled off under reduced pressure, thereby
obtaining a product. The resulting product was identified by
1H-NMR and
19F-NMR. As a result of the quantitative analysis of the product by gas chromatography,
it was found that the compound represented by the above formula (3-5-3) was a principal
component.
(Synthesis Example (D-2): Synthesis of compound represented by the above formula (3-5-4))
[0351] A product containing the compound represented by the above formula (3-5-4) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(D-1) except that an iodinated material represented by the following formula (D-e-2)
was used instead of the iodinated material represented by the above formula (D-e-1)
described in Synthesis Example (D-1).
(Synthesis Example (D-3): Synthesis of compound represented by the above formula (3-5-5))
[0352] A product containing the formula represented by the above formula (3-5-5) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(D-1) except that an iodinated material represented by the following formula (D-e-3)
was used instead of the iodinated material represented by the above formula (D-e-1)
described in Synthesis Example (D-1).
(Synthesis Example (D-4): Synthesis of compound represented by the above formula (3-5-6))
[0353] A product containing the compound represented by the above formula (3-5-6) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(D-1) except that an iodinated material represented by the following formula (D-e-4)
was used instead of the iodinated material represented by the above formula (D-e-1)
described in Synthesis Example (D-1).
(Synthesis Example (D-5))
[0354] A reaction was carried out in a manner similar to that of Synthesis Example (D-1)
except that an iodinated material represented by the following formula (D-f-1):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was used instead of the iodinated material represented by the above formula (D-e-1)
described in Synthesis Example (D-1). Consequently, a product, in which a compound
represented by the following formula (D-f):
(in the above formula, 7 represents the number of repetitions of the repetitive unit)
was a principal component, was obtained.
(Production Example (D-1): Production of polymer (D-A))
[0355] In a glass flask equipped with an agitator, a reflux condenser, a dropping funnel,
a thermometer, and a gas-blowing opening, 10 parts of methyl methacrylate (hereinafter,
abbreviated as MMA) and 0.3 part of an acetone (17.5%)-toluene mixture solvent were
placed. Subsequently, a nitrogen gas was introduced into the flask and then 0.5 part
of azobisisobutyronitrile (hereinafter, abbreviated as AIBN) as a polymerization initiator
and 0.32 part of thioglycolic acid as a chain transfer agent were added to initiate
polymerization under reflux. During a time period of 4.5 hours after the initiation,
90 parts of MMA was continuously dropped. In addition, 2.08 parts of thioglycolic
acid was dissolved in 7 parts of toluene and then added every 30 minutes in nine times.
Likewise, AIBN (1.5 parts) was added every 1.5 hours in three times to carry out the
polymerization. Subsequently, the mixture was refluxed for an additional two hours,
thereby terminating the polymerization. A polymer solution of the above formula (g)
was obtained. The reaction temperature was 77 to 87°C. Part of the reaction solution
was re-precipitated with n-hexane and then dried, followed by obtaining an acid value
of 0.34 mg equivalent/g as a result of the measurement of acid value. An average number
of repetitions of the repetitive unit was about 80.
[0356] Next, part of acetone was distilled off from the above reaction solution, followed
by the addition of 0.5% of triethylamine as a catalyst and 200 ppm of hydroquinone
monomethyl ether as a polymerization-prohibiting agent. In addition, 1.2-fold molar
excess of glycidyl methacrylate was added with respect to the acid value of the polymer.
Subsequently, the reaction solution was reacted for 11 hours under reflux (about 110°C).
The reaction solution was added to 10 volumes of n-hexane and then precipitated, followed
by drying at 80°C under reduced pressure. As a result, 90 parts of a compound represented
by the above formula (d-1) was obtained.
[0357] Next, the following materials were placed in a glass flask equipped with an agitator,
a reflux condenser, a dropping funnel, a thermometer, and a gas-blowing opening and
then subjected to the introduction of a nitrogen gas, followed by reacting for 5 hours
under reflux (heated to about 100°C). 70 parts of a compound represented by the above
formula (d-1). 30 parts of a product in which a compound represented by the above
formula (3-5-3) obtained in Synthesis Example (D-1) was a principal component. 270
parts of trifluorotoluene. AIBN (0.35 part). The reaction solution was introduced
into 10 volumes of methanol and precipitated, followed by drying at 80°C under reduced
pressure. Consequently, a polymer (D-A: weight average molecular weight (Mw): 22,000)
having a repetitive structural unit represented by the above formula (1-5-3) was obtained.
[0358] The weight average molecular weight of the polymer was determined in a manner similar
to the measurement method as described above.
(Production Example (D-2): Production of polymer (D-B))
[0359] The reaction and the process were carried out by the same procedures as those of
Production Example (D-1) except that the compound represented by the above formula
(3-5-3) was replaced with a product in which the compound represented by the above
formula (3-5-4) obtained in Synthesis Example (D-2) was a principal component. Consequently,
a polymer (D-B: weight average molecular weight 23,000) having the repetitive structural
unit represented by the above formula (1-5-4) was obtained.
(Production Example (D-3): Production of polymer (D-C))
[0360] The reaction and the process were carried out by the same procedures as those of
Production Example (D-1) except that the compound represented by the above formula
(3-5-3) was replaced with a product in which the compound represented by the above
formula (3-5-5) obtained in Synthesis Example (D-3) was a principal component. Consequently,
a polymer (D-C: weight average molecular weight 20,000) having the repetitive structural
unit represented by the above formula (1-5-5) was obtained.
(Production Example (D-4): Production of polymer (D-D))
[0361] The reaction and the process were carried out by the same procedures as those of
Production Example (D-1) except that the compound represented by the above formula
(3-5-3) was replaced with a product in which the compound represented by the above
formula (3-5-6) obtained in Synthesis Example (D-4) was a principal component. Consequently,
a polymer (D-D: weight average molecular weight 24,500) having the repetitive structural
unit represented by the above formula (1-5-6) was obtained.
(Production Example (D-5): Production of polymer (B-E)) (comparative example)
[0362] The reaction and the process were carried out by the same procedures as those of
Production Example (D-1) except that the compound represented by the above formula
(3-3-2) was replaced with a product in which the compound represented by the above
formula (D-f) obtained in Synthesis Example (D-5) was a principal component. Consequently,
a polymer (D-E: weight average molecular weight 21,000) having the repetitive structural
unit represented by the following formula (D-f-2) was obtained:
(in the above formula, 7 represents the number of repetitions of the repetitive unit).
(Example (D-1))
[0363] A conductive support used was an aluminum cylinder (JIS-A3003, aluminum alloy ED
tube, manufactured by Showa Aluminum Corporation) with 260.5 mm in length and 30 mm
in diameter obtained by heat extrusion under the environment with a temperature of
23°C and a humidity of 60%RH.
[0364] The following materials were dispersed with a sand mill with 1-mm-diameter glass
beads for 3 hours, thereby preparing a dispersion solution. TiO
2 particles covered with oxygen-deficient SnO
2 as conductive particles (power resistivity: 80 Ω·cm, SnO
2 coverage rate (mass ratio): 50%), 6.6 parts. A phenol resin (trade name: Plyophen
J-325, manufactured by Dainippon Ink & Chemicals, Incorporated. 60% resin solid) as
a resin binder, 5.5 parts. Methoxy propanol as a solvent, 5.9 parts.
[0365] The following materials were added to the dispersion solution, and the whole was
stirred, thereby preparing a conductive-layer coating solution. Silicone resin particles
(trade name: Tospal 120, GE Toshiba Silicones, average particle size: 2 µm) as a surface-roughness
imparting agent, 0.5 part. Silicone oil (trade name: SH28PA, manufactured by Dow Corning
Toray Silicone Co., Ltd.) as a leveling agent, 0.001 part.
[0366] The support was dip-coated with the conductive-layer coating solution and the whole
was dried at a temperature of 140°C for 30 minutes to heat-curing, thereby forming
a conductive layer of 15 µm in average film thickness at a position of 130 mm from
the upper side of the support.
[0367] The conductive layer was dip-coated with the following intermediate-layer coating
solution and then the whole was dried at a temperature of 100°C for 10 minutes, thereby
forming an intermediate layer of 0.5 µm in average film thickness at a position of
130 mm from the upper end of the support. An intermediate-layer coating solution prepared
by dissolving N-methoxy methylated nylon (trade name: Toresin EF-30T, manufactured
by Teikoku Chemical Industry Co., Ltd.), 4 parts, and a copolymer nylon resin (Amilan
CM8000, manufactured by Toray Co., Ltd.), 2 parts, in a mixture solvent of 65 parts
of methanol and 30 parts of n-butanol.
[0368] Subsequently, the following materials were dispersed with a sand-milling device with
glass beads of 1 mm in diameter for 1 hour. Next, 250 parts of ethyl acetate was added
to the mixture, thereby preparing a charge-generating layer coating solution. Hydroxy
gallium phthalocyanine in crystal form with strong peaks at Bragg angles (2θ ± 0.2°)
in CuKα-characteristic X-ray diffraction of 7.5°, 9.9°, 16.3°, 18.6°, 25.1°, and 28.3°,
10 parts. Polyvinyl butyral (trade name: S-LEX BX-1, manufactured by Sekisui Chemical,
Co., Ltd.), 5 parts. Cyclohexanone, 250 parts.
[0369] The intermediate layer was dip-coated with the charge-generating layer coating solution
and then the whole was dried at a temperature of 100°C for 10 minutes, thereby forming
a charge-generating layer of 0.16 µm in average film thickness at a position of 130
mm from the upper end of the support.
[0370] Next, the following materials were dissolved in a mixture solvent of 30 parts of
dimethoxy methane and 70 parts of chlorobenzene, thereby preparing a coating solution
containing a charge-transporting substance. A charge-transporting substance having
a structure represented by the above formula (CTM-1), 10 parts. A polycarbonate resin
(Iupilon Z-400, manufactured by Mitsubishi Engineering-Plastics Corporation) [viscosity
average molecular weight (Mv): 39,000] formed of a repetitive structural unit represented
by the above formula (P-1) as a binder resin, 10 parts. A polymer produced in Production
Example (D-1) (D-A: 0.2 part).
[0371] The charge-generating layer was dip-coated with the charge-transporting layer coating
solution thus prepared and then the whole was dried at a temperature of 120°C for
30 minutes. Consequently, a charge-transporting layer with an average film thickness
of 17 µm at a position of 130 mm from the upper end of the support was formed.
[0372] Consequently, the electrophotographic photosensitive member in which the charge-transporting
layer was provided as a surface layer was prepared.
[0373] The electrophotographic photosensitive member thus prepared was evaluated for initial
blade-curling
*1 and electrophotographic properties
*2. The results are shown in Table 1.
*1: Evaluation method for initial blade-curling
[0374] The electrophotographic photosensitive member thus prepared, the main body of a laser
beam printer LBP-2510 manufactured by Canon Co. Ltd., and a process cartridge of the
main body were placed under the environment with a temperature of 35°C and a humidity
of 80%RH for 15 hours. After that, under the environment, the electrophotographic
photosensitive member thus prepared was mounted on the process cartridge, followed
by continuous output of 20 sheets of a solid white image. During the printing, whether
a curling trouble of a cleaning blade occurred was observed (the evaluation was performed
on four stations (four new electrophotographic photosensitive members and four new
process cartridges were prepared for the respective colors), and "F" was written in
Table 1 when the curling trouble occurred even only once or "A" was written when no
trouble occurred at all).
*2: Evaluation method for electrophotographic properties
[0375] The prepared electrophotographic photosensitive member, the main body of the laser
beam printer LBP-2510 manufactured by Canon Co., Ltd., and tools for measuring a surface
potential were placed under the environment with a temperature of 25°C and a humidity
of 50%RH (normal temperature and normal humidity) for 15 hours. Further, the tools
for measuring the surface potential were those (the toner, the developing rollers,
and the cleaning blade were removed) used for placing a probe for surface-potential
measurement of an electrophotographic photosensitive member on the developing roller
position of the process cartridge of the LBP-2510. After that, under the same environment,
the tools for measuring the surface potential of the electrophotographic photosensitive
member were attached to the member, and the surface potential of the electrophotographic
photosensitive member was then measured without sheet-feeding under the condition
in which a belt unit for electrostatic image transfer was removed. By the way, the
tools for measuring the surface potential were mounted on the station of a cyan process
cartridge in the main body and the measurement was then carried out.
[0376] A potential measurement method was carried out as described below. First, an exposure
part potential (VI: a potential at first round after exposure of the electrophotographic
photosensitive member with whole surface exposure after electrification) was measured.
Next, a pre-exposure after-potential (Vr: a potential at first cycle (second round
after electrification) after the pre-exposure without image exposure with electrification
at only first round of the electrophotographic photosensitive member) was then measured.
Subsequently, a cycle of electrification/whole-surface image exposure/pre-exposure
was repeated 1,000 times (1K cycles). After that, the pre-exposure after-potential
(in the table, represented by Vr (1K)) was measured again.
[0377] Those results were shown in Table 4.
(Example (D-2))
[0378] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) used in the charge-transporting
layer coating solution in Example (D-1) was replaced with the polymer (D-B) produced
in Production Example (D-2). The results are shown in Table 4.
(Example (D-3))
[0379] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) used in the charge-transporting
layer coating solution in Example (D-1) was replaced with the polymer (D-C) produced
in Production Example (D-3). The results are shown in Table 4.
(Example (D-4))
[0380] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) used in the charge-transporting
layer coating solution in Example (D-1) was replaced with the polymer (D-D) produced
in Production Example (D-4). The results are shown in Table 4.
(Example (D-5))
[0381] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except for the following change in Example (D-1).
The results are shown in Table 4.
[0382] The polycarbonate resin formed of a repetitive structural unit represented by the
above formula (P-1), the binder resin of the charge-transporting layer, was replaced
with a polyarylate resin having a repetitive structural unit represented by the above
formula (P-2)(weight average molecular weight (Mw): 120,000).
[0383] By the way, a molar ratio between a terephthalic acid structure and an isophthalic
acid structure in the above polyarylate resin (tetraphthalic acid structure: isophthalic
acid structure) was 50:50.
(Example (D-6))
[0384] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-6) except that hydroxy gallium phthalocyanine as the
charge-generating substance of the charge-generating layer in Example (D-5) was replaced
with oxytitanium phthalocyanine (TiOPc) below. The results are shown in Table 4. TiOPc
with strong peaks at Bragg angles 2θ ± 0.2° in CuKα-characteristic X-ray diffraction
of 9.0°, 14.2°, 23.9°, and 27.1°.
(Example (D-7))
[0385] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-7) except that the charge-transporting substance represented
by the above formula (CTM-1) used in the charge-transporting layer coating solution
in Example (D-6) was replaced with a charge-transporting substance represented by
the above formula (CTM-2) and a charge-transporting substance represented by the following
formula (CTM-3). 5 parts of each charge-transporting substance was used. The results
are shown in Table 4.
(Comparative Example (D-1))
[0386] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) was not contained in
the charge-transporting layer coating solution in Example (D-1) The results are shown
in Table 4.
(Comparative Example (D-2))
[0387] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) used in the charge-transporting
layer coating solution in Example (D-1) was replaced with 2,6-di-tert-butyl-p-cresol
(BHT). The results are shown in Table 4.
(Comparative Example (D-3))
[0388] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) used in the charge-transporting
layer coating solution in Example (D-1) was replaced with the polymer (D-E) produced
in Production Example (D-5). The results are shown in Table 4.
(Comparative Example (D-4))
[0389] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (D-1) except that the polymer (D-A) used in the charge-transporting
layer coating solution in Example (D-1) was replaced with a compound (trade name:
Alon GF300, manufactured by Toagosei Co., Ltd.). The results are shown in Table 4.
Table 4
|
|
Initial blade-curling |
Initial electrophotograp hic properties |
After endurance |
V1(-V) |
Vr(-V) |
Vr(1K)(-V) |
Example D-1 |
Polymer D-A |
A |
125 |
35 |
45 |
Example D-2 |
Polymer D-B |
A |
125 |
35 |
45 |
Example D-3 |
Polymer D-C |
A |
120 |
35 |
45 |
Example D-4 |
Polymer D-D |
A |
120 |
30 |
40 |
Example D-5 |
Polymer D-A |
A |
125 |
35 |
45 |
Example D-6 |
Polymer D-A |
A |
125 |
35 |
45 |
Example D-7 |
Polymer D-A |
A |
125 |
35 |
45 |
|
|
|
|
|
|
Comparative Example D-1 |
- |
F |
120 |
25 |
30 |
Comparative Example D-2 |
BHT |
F |
135 |
45 |
75 |
Comparative Example D-3 |
Polymer D-E |
A |
120 |
40 |
60 |
Comparative Example D-4 |
Alon GF300 |
A |
125 |
35 |
55 |
[0390] As is evident from the above results, Examples (D-1) to (D-7) of the present invention
and Comparative Examples (D-1) and (D-2) are compared with each other, whereby the
following fact is found. Blade-curling at an initial stage can be prevented by producing
an electrophotographic photosensitive member using a compound having a repetitive
unit according to the present invention as a constitutional component of a coating
solution for the formation of a surface layer. As a result, an electrophotographic
photosensitive member avoiding such a trouble can be provided.
[0391] In addition, by comparing Examples (D-1) to (D-7) of the present invention and Comparative
Example (D-3) with each other, a structure in which an alkyl group having a fluorine
atom and an alkylene group having a fluorine atom are coupled with each other through
oxygen or a structure in which an alkylene group having a fluorine atom and an alkylene
group having a fluorine atom are coupled with each other through oxygen in a compound
having a repetitive unit according to the present invention is shown to be excellent
in repetitive property out of the electrophotographic properties.
[0392] Further, Examples (D-1) to (D-7) of the present invention and Comparative Example
(D-4) are compared with each other, whereby the following fact is found. An electrophotographic
photosensitive member is produced by using a compound having a repetitive unit according
to the present invention as a structural component of a coating solution for the formation
of a surface layer. As a result, the member is more excellent in the repetitive property
out of the electrophotographic properties than that in the case where the compound
of Comparative Example 4 is used.
(Synthesis Example (E-1): Synthesis of compound represented by the above formula (3-6-2))
[0393] 0.5 part of an iodinated material represented by the following formula (E-e-1):
F
3C-CF
2-CF
2-CF
2-CH
2-CH
2-I (E-e-1)
and 20 parts of ion-exchanged water were incorporated into a deaerated autoclave,
followed by heating the inside of the autoclave up to 300°C to carry out a conversion
reaction of iodine to a hydroxyl group at a gauge pressure of 9.2 MPa for 4 hours.
[0394] After the end of the reaction, 20 parts of diethyl ether were added to the reaction
mixture. After the mixture had been separated into two phases, 0.2 part of magnesium
sulfate was placed in an ether phase and the magnesium sulfate was then removed by
filtration, thereby obtaining a hydroxyl compound of the above formula (E-e-1). The
hydroxyl compound was subjected to column chromatography to separate and remove components
other than principal components, whereby the hydroxyl compound was obtained. Subsequently,
100 parts of the hydroxyl compound, 50 parts of acrylic acid, 5 parts of hydroquinone,
5 parts of p- toluenesulfonic acid, and 200 parts of toluene were introduced into
a glass flask equipped with an agitator, a condenser, and a thermometer. After that,
the glass flask was heated up to 110°C and the reaction was then continued until the
raw material, the hydroxyl compound, disappeared. After the completion of the reaction,
the mixture was diluted with 200 parts of toluene, washed with an aqueous sodium hydroxide
solution twice, and then washed with ion-exchanged water three times. Subsequently,
toluene was distilled off under reduced pressure, thereby obtaining a product. The
resulting product was identified by
1H-NMR and
19F-NMR. As a result of the quantitative analysis of the product by gas chromatography,
it was found that the principal component of the product was the compound represented
by the above formula (3-6-2).
(Synthesis Example (E-2): Synthesis of compound represented by the above formula (3-6-3))
[0395] A product containing the compound represented by the above formula (3-6-3) as a principal
component was obtained by carrying out the same reaction as that of Synthesis Example
(E-1) except that an iodinated material represented by the following formula (E-e-2)
was used instead of the iodine compound represented by the above formula (E-e-1) described
in Synthesis Example (E-1).
F
3C-CF
2-CF
2-CF
2-CH
2-CH
2-CH
2-I (E-e-2)
(Synthesis Example (E-3): Synthesis of compound represented by the above formula (3-6-10))
[0396] A product containing the compound represented by the above formula (3-6-10) as a
principal component was obtained by carrying out the same reaction as that of Synthesis
Example (E-1) except that an iodinated material represented by the following formula
(E-e-3) was used instead of the iodinated material represented by the above formula
(E-e-1) described in Synthesis Example (E-1).
F
3C-CF
2-CF
2-CF
2-CF
2-CF
2-CH
2-CH
2-I (E-e-3)
(Synthesis Example (E-4): Synthesis of compound represented by the above formula (3-6-11))
[0397] A product containing the compound represented by the above formula (3-6-11) as a
principal component was obtained by carrying out the same reaction as that of Synthesis
Example (E-1) except that an iodinated material represented by the following formula
(E-e-4) was used instead of the iodinated material represented by the above formula
(E-e-1) described in Synthesis Example (E-1).
F
3C-CF
2-CF
2-CF
2-CF
2-CF
2-CH
2-CH
2-CH
2-I (E-e-4)
(Synthesis Example (E-5))
[0398] Instead of the iodinated material represented by the above formula (E-e-1) described
in Synthesis Example (E-1), an iodinated material represented by the following formula
(E-f-1-a) :
(in the above formula, 7 represents the number of repetitions of the repetitive unit
of the substituent - CF
2-) was used and reacted in a manner similar to Synthesis Example (E-1). As a result,
a product having a compound represented by the following formula (E-f-1) :
(in the above formula, 7 represents the number of repetitions of the repetitive unit
of the substituent - CF
2-) as a principal component was obtained.
(Synthesis Example (E-6))
[0399] Instead of the iodinated material represented by the above formula (E-e-1) described
in Synthesis Example (E-1), an iodinated material represented by the following formula
(E-f-2-a):
(in the formula, 9 represents the number of repetitions of the repetitive unit of
the substituent -CF
2-) was used and reacted in a manner similar to Synthesis Example (E-1). As a result,
a product having a compound represented by the following formula (E-f-2):
(in the formula, 9 represents the number of repetitions of the repetitive unit of
the substituent -CF
2-) as a principal component was obtained.
(Synthesis Example (E-7))
[0400] Instead of the iodinated material represented by the above formula (E-e-1) described
in Synthesis Example (E-1), an iodinated material represented by the following formula
(E-f-3-a):
F
3C-CF
2-CH
2CH
2-I (E-f-3-a)
was used and reacted in a manner similar to Synthesis Example (E-1). As a result,
a product having a compound represented by the following formula (E-f-3):
as a principal component was obtained.
(Production Example (E-1): Production of polymer (E-A))
[0401] In a glass flask equipped with an agitator, a reflux condenser, a dropping funnel,
a thermometer, and a gas-blowing opening, 10 parts of methyl methacrylate (hereinafter,
abbreviated as MMA) and 0.3 part of an acetone (17.5%)-toluene mixture solvent were
introduced. Subsequently, a nitrogen gas was introduced into the flask and then 0.5
part of 2,2'-azobisisobutyronitrile (hereinafter, abbreviated as AIBN) as a polymerization
initiator and 0.32 part of thioglycolic acid as a chain transfer agent were added
to initiate polymerization under reflux. During a time period of 4.5 hours after the
initiation, 90 parts of MMA was continuously dropped. In addition, 2.08 parts of thioglycolic
acid was dissolved in 7 parts of toluene and then added every 30 minutes in nine times.
Likewise, 1.5 parts of AIBN was added every 1.5 hours in three times to carry out
the polymerization. Subsequently, the mixture was refluxed for an additional two hours,
thereby terminating the polymerization. A polymer solution of the above formula (g)
was obtained. The reaction temperature was 77 to 87°C.
[0402] Part of the reaction solution was re-precipitated with n-hexane and then dried, followed
by obtaining an acid value of 0.34 mg equivalent/g as a result of the measurement
of acid value. An average number of repeating the repetitions of unit was about 80.
[0403] Next, part of acetone was distilled off from the above reaction solution, followed
by the addition of 0.5% of triethyl amine as a catalyst and 200 ppm of hydroquinone
monomethyl ether as a polymerization-prohibiting agent. In addition, 1.2-fold molar
excess of glycidyl methacrylate was added with respect to the acid value of the polymer.
Subsequently, the reaction solution was reacted for 11 hours under reflux (about 110°C).
The reaction solution was added to 10 volumes of n-hexane and then precipitated, followed
by drying at 80°C under reduced pressure. As a result, 90 parts of a compound represented
by the above formula (d-1) was obtained.
[0404] Next, in a glass flask equipped with an agitator, a reflux condenser, a dropping
funnel, a thermometer, and a gas-blowing opening, the following components were introduced:
[0405] A compound represented by the above formula (d-1), 70 parts.
[0406] A product containing a compound obtained in Synthesis Example (E-1) and represented
by the above formula (3-6-2) as a principal component, 30 parts.
Trifluorotoluene, 270 parts.
AIBN, 0.35 part.
[0407] A nitrogen gas was introduced into the flask and then the mixture was reacted for
5 hours under reflux (heated to about 100°C). The reaction solution was placed in
10 volumes of methanol and precipitated, followed by drying at 80°C under reduced
pressure. Consequently, a polymer (E-A) having a repetitive structural unit represented
by the above formula (1-6-2) was obtained. By the way, the weight average molecular
weight of the polymer (E-A) was 22,000.
[0408] The weight average molecular weight of the polymer was determined in a manner similar
to the above measurement method.
(Production Example (E-2): Production of polymer (E-B))
[0409] A polymer (E-B) having a repetitive structural unit represented by the above formula
(1-6-3) was obtained by a reaction and a process carried out by the same procedures
as those of Production Example (E-1) except that the compound represented by the above
formula (3-6-2) was replaced with a product in which the compound represented by the
above formula (3-6-3) obtained in Synthesis Example (E-2) was a principal component.
By the way, the weight average molecular weight of the polymer (E-B) was 20,000.
(Production Example (E-3): Production of polymer (E-C))
[0410] A polymer (E-C) having a repetitive structural unit represented by the above formula
(1-6-10) was obtained by a reaction and a process carried out by the same procedures
as those of Production Example (E-1) except that the compound represented by the above
formula (3-6-2) was replaced with a product in which the compound represented by the
above formula (3-6-10) obtained in Synthesis Example (E-3) was a principal component.
By the way, the weight average molecular weight of the polymer (E-C) was 23,000.
(Production Example (E-4): Production of polymer (E-D))
[0411] A polymer (E-D) having a repetitive structural unit represented by the above formula
(1-6-11) was obtained by a reaction and a process carried out by the same procedures
as those of Production Example (E-1) except that the compound represented by the above
formula (3-6-2) was replaced with a product in which the compound represented by the
above formula (3-6-11) obtained in Synthesis Example (E-4) was a principal component.
By the way, the weight average molecular weight of the polymer (E-D) was 22,600.
(Production Example (E-5): Production of polymer (E-E))
[0412] A polymer (E-E) was obtained by a reaction and a process carried out by the same
procedures as those of Production Example (E-1) except that each of the following
components was used instead of 30 parts of the compound represented by the above formula
(3-6-2). The polymer (E-E) included a repetitive structural unit represented by the
above formula (1-6-2) and a repetitive structural unit represented by the above formula
(1-6-10) in a molar ratio of 70:30. By the way, the weight average molecular weight
of the polymer (E-E) was 22,900.
[0413] A product containing a compound obtained in Synthesis Example (E-1) and represented
by the above formula (3-6-2) as a principal component, 21 parts.
[0414] A product containing a compound obtained in Synthesis Example (E-3) and represented
by the above formula (3-6-10) as a principal component, 9 parts.
(Production Example (E-6): Production of polymer (E-F))
[0415] A polymer (E-F) was obtained by a reaction and a process carried out by the same
procedures as those of Production Example (E-1) except that each of the following
components was used instead of 30 parts of the compound represented by the above formula
(3-6-2). The polymer (E-F) included a repetitive structural unit represented by the
above formula (1-6-2) and a repetitive structural unit represented by the above formula
(1-6-10) in a molar ratio of 50:50. By the way, the weight average molecular weight
of the polymer (E-F) was 24,000.
[0416] A product containing a compound obtained in Synthesis Example (E-1) and represented
by the above formula (3-6-2) as a principal component, 15 parts.
[0417] A product containing a compound obtained in Synthesis Example (E-3) and represented
by the above formula (3-6-10) as a principal component, 15 parts.
(Production Example (E-7): Production of polymer (E-G))
[0418] A polymer (E-G) was obtained by a reaction and a process carried out by the same
procedures as those of Production Example (E-1) except that each of the following
components was used instead of 30 parts of the compound represented by the above formula
(3-6-2). The polymer (E-G) included a repetitive structural unit represented by the
above formula (1-6-2) and a repetitive structural unit represented by the above formula
(3-6-10) in a molar ratio of 30:70. By the way, the weight average molecular weight
of the polymer (EG) was 25,000.
[0419] A product containing a compound obtained in Synthesis Example (E-1) and represented
by the above formula (3-6-2) as a principal component, 9 parts.
[0420] A product containing a compound obtained in Synthesis Example (E-3) and represented
by the above formula (3-6-10) as a principal component, 21 parts.
(Production Example (E-8): Production of polymer (E-H))
[0421] A polymer (E-H) was obtained by a reaction and a process carried out by the same
procedures as those of Production Example (E-1) except that each of the following
components was used instead of 30 parts of the compound represented by the above formula
(3-6-2). As a result, the polymer (E-H) included a repetitive structural unit represented
by the following formula (E-f-3-b) :
, a repetitive structural unit represented by the above formula (1-6-2), and a repetitive
structural unit represented by the above formula (1-6-10) in a molar ratio of 3:67:30.
By the way, the weight average molecular weight of the polymer (E-H) was 22,000.
[0422] A product containing a compound obtained in Synthesis Example (E-7) and represented
by the above formula (E-f-3) as a principal component, 1 part.
[0423] A product containing a compound obtained in Synthesis Example (E-1) and represented
by the above formula (3-6-2) as a principal component, 20 parts.
[0424] A product containing a compound obtained in Synthesis Example (E-3) and represented
by the above formula (3-6-10) as a principal component, 9 parts.
(Production Example (E-9): Production of polymer (E-I))
[0425] A polymer (E-I) was obtained by a reaction and a process carried out by the same
procedures as those of Production Example (E-1) except that each of the following
components was used instead of 30 parts of the compound represented by the above formula
(3-6-2). As a result, the polymer (E-I) included a repetitive structural unit represented
by the above formula (1-6-2), a repetitive structural unit represented by the above
formula (1-6-10), and a repetitive structural unit represented by the following formula
(E-f-1-b):
(in the above formula, 7 represents the number of repetitions of the repetitive unit
of the substituent - CF
2-) in a molar ratio of 30:67:3. By the way, the weight average molecular weight of
the polymer (E-I) was 18,600.
[0426] A product containing a compound obtained in Synthesis Example (E-1) and represented
by the above formula (3-6-2) as a principal component, 9 parts.
[0427] A product containing a compound obtained in Synthesis Example (E-3) and represented
by the above formula (3-6-10) as a principal component, 20 parts.
[0428] A product containing a compound obtained in Synthesis Example (E-5) and represented
by the above formula (E-f-1) as a principal component, 1 part.
(Production Example (E-10): Production of polymer (E-J)) (comparative example)
[0429] A polymer (E-J) having a repetitive structural unit represented by the above formula
(E-f-1-b) was obtained by a reaction and a process carried out by the same procedures
as those of Production Example (E-1) except that the compound represented by the above
formula (3-6-2) was replaced with a product in which the compound represented by the
above formula (E-f-1) obtained in Synthesis Example (E-5) was a principal component.
By the way, the weight average molecular weight of the polymer (E-J) was 24,000.
(Production Example (E-11): Production of polymer (E-K)) (comparative example)
[0430] A polymer (E-K) was obtained by a reaction and a process carried out by the same
procedures as those of Production Example (E-1) except that the compound represented
by the above formula (3-6-2) was replaced with a product in which the compound represented
by the above formula (E-f-2) obtained in Synthesis Example (E-6) was a principal component.
As a result, the polymer (E-K) had a repetitive structural unit represented by the
following formula (E-f-2-b):
(in the above formula, 9 represents the number of repetitions of the repetitive unit
of the substituent - CF
2-). By the way, the weight average molecular weight of the polymer (E-K) was 25,000.
(Production Example (E-12): Production of polymer (EL)) (comparative example)
[0431] A polymer (E-L) having a repetitive structural unit represented by the above formula
(E-f-3-b) was obtained by a reaction and a process carried out by the same procedures
as those of Production Example (E-1) except that the compound represented by the above
formula (3-6-2) was replaced with a product in which the compound represented by the
above formula (E-f-3) obtained in Synthesis Example (E-7) was a principal component.
By the way, the weight average molecular weight of the polymer (E-L) was 21,700.
(Example (E-1))
[0432] A conductive support used was an aluminum cylinder (JIS-A3003, aluminum alloy ED
tube, manufactured by Showa Aluminum Corporation) with 260.5 mm in length and 30 mm
in diameter obtained by heat extrusion under the environment with a temperature of
23°C and a humidity of 60%RH.
[0433] The following materials were dispersed with a sand mill with 1-mm-diameter glass
beads for 3 hours, thereby preparing a dispersion solution. TiO
2 particles covered with oxygen-deficient SnO
2 as conductive particles (power resistivity: 80 Ω·cm, SnO
2 coverage rate (mass ratio): 50%), 6.6 parts. A phenol resin (trade name: Plyophen
J-325, manufactured by Dainippon Ink & Chemicals, Incorporated. 60% resin solid) as
a resin binder, 5.5 parts. Methoxy propanol as a solvent, 5.9 parts.
[0434] The following materials were added to the dispersion solution, and the whole was
stirred, thereby preparing a conductive-layer coating solution. Silicone resin particles
(trade name: Tospal 120, GE Toshiba Silicones, average particle size: 2 µm) as a surface-roughness
imparting agent, 0.5 part. Silicone oil (trade name: SH28PA, manufactured by Dow Corning
Toray Silicone Co., Ltd.) as a leveling agent, 0.001 part.
[0435] The support was dip-coated with the conductive-layer coating solution and the whole
was dried at a temperature of 140°C for 30 minutes to heat-curing, thereby forming
a conductive layer of 15 µm in average film thickness at a position of 130 mm from
the upper side of the support.
[0436] The conductive layer was dip-coated with the following intermediate-layer coating
solution and then the whole was dried at a temperature of 100°C for 10 minutes, thereby
forming an intermediate layer of 0.5 µm in average film thickness at a position of
130 mm from the upper end of the support. An intermediate-layer coating solution prepared
by dissolving N-methoxy methylated nylon (trade name: Toresin EF-30T, manufactured
by Teikoku Chemical Industry Co., Ltd.), 4 parts, and a copolymer nylon resin (Amilan
CM8000, manufactured by Toray Co., Ltd.), 2 parts, in a mixture solvent of 65 parts
of methanol and 30 parts of n-butanol.
[0437] Subsequently, the following materials were dispersed with a sand-milling device with
glass beads of 1 mm in diameter for 1 hour. Next, 250 parts of ethyl acetate was added
to the mixture, thereby preparing a charge-generating layer coating solution. Hydroxy
gallium phthalocyanine in crystal form with strong peaks at Bragg angles (2θ ± 0.2°)
in CuKα-characteristic X-ray diffraction of 7.5°, 9.9°, 16.3°, 18.6°, 25.1°, and 28.3°,
10 parts. Polyvinyl butyral (trade name: S-LEX BX-1, manufactured by Sekisui Chemical,
Co., Ltd.), 5 parts. Cyclohexanone, 250 parts.
[0438] The intermediate layer was dip-coated with the charge-generating layer coating solution
and then the whole was dried at a temperature of 100°C for 10 minutes, thereby forming
a charge-generating layer of 0.16 µm in average film thickness at a position of 130
mm from the upper end of the support. The polymer (E-A) produced in Production Example
(E-1), 0.2 part.
[0439] The charge-generating layer was dip-coated with the charge-transporting layer coating
solution thus prepared and then the whole was dried at a temperature of 120°C for
30 minutes. Consequently, a charge-transporting layer with an average film thickness
of 17 µm at a position of 130 mm from the upper end of the support was formed.
[0440] Consequently, the electrophotographic photosensitive member in which the charge-transporting
layer was provided as a surface layer was prepared.
[0441] The electrophotographic photosensitive member thus prepared was evaluated for initial
blade-curling
*1 and electrophotographic properties
*2. The results are shown in Table 1.
*1: Evaluation method for initial blade-curling
[0442] The electrophotographic photosensitive member thus prepared, the main body of a laser
beam printer LBP-2510 manufactured by Canon Co. Ltd., and a process cartridge of the
main body were placed under the environment with a temperature of 35°C and a humidity
of 80%RH for 15 hours. After that, under the environment, the electrophotographic
photosensitive member thus prepared was mounted on the process cartridge, followed
by continuous output of 20 sheets of a solid white image. During the printing, whether
a curling trouble of a cleaning blade occurred was observed (the evaluation was performed
on four stations (four new electrophotographic photosensitive members and four new
process cartridges were prepared for the respective colors), and "F" was written in
Table 1 when the curling trouble occurred even only once or "A" was written when no
trouble occurred).
*2: Evaluation method for electrophotographic properties
[0443] The prepared electrophotographic photosensitive member, the main body of the laser
beam printer LBP-2510 manufactured by Canon Co., Ltd., and tools for measuring a surface
potential were placed under the environment with a temperature of 25°C and a humidity
of 50%RH (normal temperature and normal humidity) for 15 hours. Further, the tools
for measuring the surface potential were those (the toner, the developing rollers,
and the cleaning blade were removed) used for placing a probe for surface-potential
measurement of an electrophotographic photosensitive member on the developing roller
position of the process cartridge of the LBP-2510. After that, under the same environment,
the tools for measuring the surface potential of the electrophotographic photosensitive
member was attached to the member, and the surface potential of the electrophotographic
photosensitive member was then measured without sheet-feeding under the condition
in which a belt unit for electrostatic image transfer was removed. By the way, the
tools for measuring the surface potential were mounted on the station of a cyan process
cartridge in the main body and the measurement was then carried out.
[0444] A potential measurement method was carried out as described below. First, an exposure
part potential (VI: a potential at first round after exposure of the electrophotographic
photosensitive member with whole surface exposure after electrification) was measured.
Next, a pre-exposure after-potential (Vr: a potential at first cycle (second round
after electrification) after the pre-exposure without image exposure with electrification
at only first round of the electrophotographic photosensitive member) was then measured.
Subsequently, a cycle of electrification/whole-surface image exposure/pre-exposure
was repeated 1,000 times (1K cycles). After that, the pre-exposure after-potential
(in the table, represented by Vr (1K)) was measured again.
[0445] Those results were shown in Table 5.
(Example (E-2) to (E-9))
[0446] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-1) except that the polymer (E-A) used in the charge-transporting
layer coating solution in Example (E-1) was replaced with a polymer represented in
Table 5. The results are shown in Table 5.
(Example (E-10))
[0447] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-1) except for the following change in Example (E-1).
The results are shown in Table 5.
[0448] The polycarbonate resin formed of a repetitive structural unit represented by the
above formula (P-1), the binder resin of the charge-transporting layer, was replaced
with a polyarylate resin having a repetitive structural unit represented by the above
formula (P-2)(weight average molecular weight (Mw): 120,000).
[0449] By the way, a molar ratio between a terephthalic acid structure and an isophthalic
acid structure in the above polyarylate resin (tetraphthalic acid structure: isophthalic
acid structure) was 50:50.
(Example (E-11))
[0450] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-10) except that the polymer (E-A) used in the charge-transporting
layer coating solution in Example (E-10) was replaced with the polymer (E-B).
[0451] The results are shown in Table 5.
(Example (E-12))
[0452] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-10) except that the charge-transporting substance represented
by the above formula (CTM-1) used in the charge-transporting layer coating solution
in Example (E-10) was replaced with a charge-transporting substance represented by
the above formula (CTM-2) and a charge-transporting substance represented by the above
general formula (CTM-3) where 5 parts of each charge-transporting substance was used.
The results are shown in Table 5.
(Example (E-13))
[0453] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-12) except that the polymer (E-A) used in the charge-transporting
layer coating solution in Example (E-12) was replaced with the polymer (E-B).
[0454] The results are shown in Table 5.
(Comparative Example (E-1))
[0455] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-1) except that the polymer (E-A) was not included in
the charge-transporting layer coating solution in Example (E-1). The results are shown
in Table 5.
(Comparative Example (E-2))
[0456] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-1) except that the polymer (E-A) used in the charge-transporting
layer coating solution in Example (E-1) was replaced with 2,6-di-tert-butyl-p-cresol
(BHT). The results are shown in Table 5.
(Comparative Examples (E-3) to (E-5))
[0457] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-1) except that the polymer (E-A) used in the charge-transporting
layer coating solution in Example (E-1) was replaced with a polymer represented in
Table 5. The results are shown in Table 5.
(Comparative Example (E-6))
[0458] An electrophotographic photosensitive member was prepared and evaluated in a manner
similar to that of Example (E-1) except that the polymer (E-A) used in the charge-transporting
layer coating solution in Example (E-1) was replaced with a compound (trade name:
Alon GF300, manufactured by Toagosei Co., Ltd.). The results are shown in Table 5.
Table 5
|
|
Repetitive structural unit with fluorine atom (molar ratio) |
Initial blade-curling |
Initial electrophotographic properties |
After endurance |
V1(-V) |
Vr(-V) |
Vr(1K) (-V) |
Example E-1 |
Polymer E-A |
(1-6-2) (100) |
A |
120 |
30 |
40 |
Example E-2 |
Polymer E-B |
(1-6-3) (100) |
A |
120 |
30 |
40 |
Example E-3 |
Polymer E-C |
(1-6-10) (100) |
A |
120 |
35 |
45 |
Example E-4 |
Polymer E-D |
(1-6-11) (100) |
A |
120 |
35 |
45 |
Example E-5 |
Polymer E-E |
(1-6-2) (70)
(1-6-10) (30) |
A |
125 |
35 |
45 |
Example E-6 |
Polymer E-F |
(1-6-2) (50)
(1-6-10) (50) |
A |
125 |
35 |
45 |
Example E-7 |
Polymer E-G |
(1-6-2) (30)
(1-6-10) (70) |
A |
125 |
35 |
45 |
Example E-8 |
Polymer E-H |
(E-f-3-b) (3)
(1-6-2) (67)
(1-6-10) (30) |
A |
120 |
35 |
45 |
Example E-9 |
Polymer E-I |
(E-f-1-b) (3)
(1-6-2) (30)
(1-6-10) (67) |
A |
120 |
35 |
45 |
Example E-10 |
Polymer E-A |
(1-6-2) (100) |
A |
120 |
25 |
30 |
Example E-11 |
Polymer E-B |
(1-6-3)(100) |
A |
120 |
25 |
30 |
Example E-12 |
Polymer E-A |
(1-6-2) (100) |
A |
120 |
25 |
30 |
Example E-13 |
Polymer E-B |
(1-6-3)(100) |
A |
120 |
25 |
30 |
|
|
|
|
|
|
|
Comparative Example E-1 |
- |
|
F |
120 |
25 |
30 |
Comparative Example E-2 |
BHT |
|
F |
135 |
45 |
75 |
Comparative Example E-3 |
Polymer E-J |
(E-f-1-b)(100) |
A |
120 |
40 |
60 |
Comparative Example E-4 |
Polymer E-K |
(E-f-2-b)(100) |
A |
140 |
45 |
70 |
Comparative Example E-5 |
Polymer E-L |
(E-f-3-b)(100) |
F |
125 |
40 |
65 |
Comparative Example E-6 |
Alon GF300 |
|
A |
125 |
35 |
55 |
[0459] As is evident from the above results, Examples (E-1) to (E-13) of the present invention
and Comparative Examples (E-1) and (E-2) are compared with each other, whereby the
following fact is found. Blade-curling at an initial stage can be prevented by producing
an electrophotographic photosensitive member using a compound having a repetitive
unit of the present invention as a constitutional component of a coating solution
for the formation of a surface layer. As a result, an electrophotographic photosensitive
member avoiding such a trouble can be provided.
[0460] In addition, by comparing Examples (E-1) to (E-13) of the present invention and Comparative
Examples (E-3) to (E-5) with each other, the use of a compound containing the structure
in the compound having the repetitive unit of the present invention in the range in
the present invention is shown to provide excellent repetitive property out of the
electrophotographic properties.
[0461] Further, Examples (E-1) to (E-13) of the present invention and Comparative Example
(E-6) are compared with each other, whereby the following fact is found. An electrophotographic
photosensitive member is produced by using a compound having a repetitive unit of
the present invention as a constitutional component of a coating solution for the
formation of a surface layer. As a result, the member is more excellent in the repetitive
property out of the electrophotographic properties than that in the case where the
compound of Comparative Example (E-6) is used.
[0462] The present application claims the priority of each of Japanese Patent Application
No.
2006-295889 filed October 31, 2006, Japanese Patent Application No.
2006-295885 filed October 31, 2006, Japanese Patent Application No.
2006-295890 filed October 31, 2006, Japanese Patent Application No.
2006-295882 filed October 31, 2006, Japanese Patent Application No.
2006-295886 filed October 31, 2006, and Japanese Patent Application No.
2007-257077 filed October 1, 2007, the contents of which are incorporated herein by reference.